31551158640 has 160 divisors (see below), whose sum is σ = 100443856896. Its totient is φ = 8189475840.

The previous prime is 31551158633. The next prime is 31551158671. The reversal of 31551158640 is 4685115513.

It is a happy number.

It is a super-2 number, since 2×31551158640² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

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 31 ways as a sum of consecutive naturals, for example, 1605675 + ... + 1625205.

Almost surely, 2^31551158640 is an apocalyptic number.

31551158640 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 31551158640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (50221928448).

31551158640 is an abundant number, since it is smaller than the sum of its proper divisors (68892698256).

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

31551158640 is a wasteful number, since it uses less digits than its factorization.

31551158640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19727 (or 19721 counting only the distinct ones).

The product of its (nonzero) digits is 72000, while the sum is 39.

The spelling of 31551158640 in words is "thirty-one billion, five hundred fifty-one million, one hundred fifty-eight thousand, six hundred forty".