Search a number
-
+
18906720 = 2535717331
BaseRepresentation
bin100100000011…
…1111001100000
31022120120010220
41020013321200
514320003340
61513123040
7316463430
oct110077140
938516126
1018906720
11a743998
1263b9480
133bbc911
1427222c0
1519d6ed0
hex1207e60

18906720 has 192 divisors, whose sum is σ = 72285696. Its totient is φ = 4055040.

The previous prime is 18906709. The next prime is 18906721. The reversal of 18906720 is 2760981.

It is a super-3 number, since 3×189067203 (a number of 23 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18906721) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 56955 + ... + 57285.

It is an arithmetic number, because the mean of its divisors is an integer number (376488).

Almost surely, 218906720 is an apocalyptic number.

18906720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18906720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36142848).

18906720 is an abundant number, since it is smaller than the sum of its proper divisors (53378976).

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

18906720 is a wasteful number, since it uses less digits than its factorization.

18906720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 373 (or 365 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 33.

The square root of 18906720 is about 4348.1858285956. The cubic root of 18906720 is about 266.4027667020.

The spelling of 18906720 in words is "eighteen million, nine hundred six thousand, seven hundred twenty".