31970323840 has 512 divisors, whose sum is σ = 101664460800. Its totient is φ = 9333080064.

The previous prime is 31970323787. The next prime is 31970323843. The reversal of 31970323840 is 4832307913.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 31970323793 and 31970323802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31970323843) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 38845669 + ... + 38846491.

It is an arithmetic number, because the mean of its divisors is an integer number (198563400).

Almost surely, 2^31970323840 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 31970323840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (50832230400).

31970323840 is an abundant number, since it is smaller than the sum of its proper divisors (69694136960).

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

31970323840 is a wasteful number, since it uses less digits than its factorization.

31970323840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 914 (or 902 counting only the distinct ones).

The product of its (nonzero) digits is 108864, while the sum is 40.

The spelling of 31970323840 in words is "thirty-one billion, nine hundred seventy million, three hundred twenty-three thousand, eight hundred forty".