Search a number
-
+
31122031200 = 25352134991999
BaseRepresentation
bin11100111111000001…
…001000001001100000
32222022221120222211020
4130333001020021200
51002214214444300
622144113045440
72151142620561
oct347701101140
988287528736
1031122031200
1112220636747
126046856880
132c1c98a8a0
141713480168
15c223b28a0
hex73f048260

31122031200 has 288 divisors, whose sum is σ = 109368000000. Its totient is φ = 7641630720.

The previous prime is 31122031177. The next prime is 31122031201. The reversal of 31122031200 is 213022113.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 31122031200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31122031201) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 15567801 + ... + 15569799.

It is an arithmetic number, because the mean of its divisors is an integer number (379750000).

Almost surely, 231122031200 is an apocalyptic number.

31122031200 is a gapful number since it is divisible by the number (30) 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 31122031200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (54684000000).

31122031200 is an abundant number, since it is smaller than the sum of its proper divisors (78245968800).

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

31122031200 is a wasteful number, since it uses less digits than its factorization.

31122031200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2534 (or 2521 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 15.

Adding to 31122031200 its reverse (213022113), we get a palindrome (31335053313).

The spelling of 31122031200 in words is "thirty-one billion, one hundred twenty-two million, thirty-one thousand, two hundred".