Search a number
-
+
81712125 = 3353113171
BaseRepresentation
bin1001101111011…
…01001111111101
312200202101222000
410313231033331
5131404242000
612035212513
72011353525
oct467551775
9180671860
1081712125
1142140590
1223447139
1313c0c791
14abd0685
157291000
hex4ded3fd

81712125 has 128 divisors (see below), whose sum is σ = 172523520. Its totient is φ = 37800000.

The previous prime is 81712079. The next prime is 81712151. The reversal of 81712125 is 52121718.

It is not a de Polignac number, because 81712125 - 29 = 81711613 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 1150840 + ... + 1150910.

It is an arithmetic number, because the mean of its divisors is an integer number (1347840).

Almost surely, 281712125 is an apocalyptic number.

It is an amenable number.

81712125 is an abundant number, since it is smaller than the sum of its proper divisors (90811395).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81712125 is a wasteful number, since it uses less digits than its factorization.

81712125 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137 (or 121 counting only the distinct ones).

The product of its digits is 1120, while the sum is 27.

The square root of 81712125 is about 9039.4759250744. The cubic root of 81712125 is about 433.9391510038.

It can be divided in two parts, 8171 and 2125, that added together give a triangular number (10296 = T143).

The spelling of 81712125 in words is "eighty-one million, seven hundred twelve thousand, one hundred twenty-five".

Divisors: 1 3 5 9 11 15 25 27 31 33 45 55 71 75 93 99 125 135 155 165 213 225 275 279 297 341 355 375 465 495 639 675 775 781 825 837 1023 1065 1125 1375 1395 1485 1705 1775 1917 2201 2325 2343 2475 3069 3195 3375 3875 3905 4125 4185 5115 5325 6603 6975 7029 7425 8525 8875 9207 9585 11005 11625 11715 12375 15345 15975 19525 19809 20925 21087 24211 25575 26625 33015 34875 35145 37125 42625 46035 47925 55025 58575 59427 72633 76725 79875 97625 99045 104625 105435 121055 127875 165075 175725 217899 230175 239625 275125 292875 297135 363165 383625 495225 527175 605275 653697 825375 878625 1089495 1150875 1485675 1815825 2476125 2635875 3026375 3268485 5447475 7428375 9079125 16342425 27237375 81712125