31857680928 has 96 divisors (see below), whose sum is σ = 85890430080. Its totient is φ = 10333091840.

The previous prime is 31857680917. The next prime is 31857680957. The reversal of 31857680928 is 82908675813.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (96).

It is a super-2 number, since 2×31857680928² (a number of 22 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1520701 + ... + 1541507.

It is an arithmetic number, because the mean of its divisors is an integer number (894691980).

Almost surely, 2^31857680928 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31857680928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42945215040).

31857680928 is an abundant number, since it is smaller than the sum of its proper divisors (54032749152).

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

31857680928 is a wasteful number, since it uses less digits than its factorization.

31857680928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21250 (or 21242 counting only the distinct ones).

The product of its (nonzero) digits is 5806080, while the sum is 57.

The spelling of 31857680928 in words is "thirty-one billion, eight hundred fifty-seven million, six hundred eighty thousand, nine hundred twenty-eight".