31398664320 has 384 divisors, whose sum is σ = 114582312000. Its totient is φ = 7900913664.

The previous prime is 31398664307. The next prime is 31398664333. The reversal of 31398664320 is 2346689313.

31398664320 is a `hidden beast` number, since 3 + 139 + 86 + 6 + 432 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (31398664307) and next prime (31398664333).

It is a tau number, because it is divible by the number of its divisors (384).

It is a super-2 number, since 2×31398664320² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 41477382 + ... + 41478138.

Almost surely, 2^31398664320 is an apocalyptic number.

31398664320 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 31398664320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (57291156000).

31398664320 is an abundant number, since it is smaller than the sum of its proper divisors (83183647680).

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

31398664320 is a wasteful number, since it uses less digits than its factorization.

31398664320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1180 (or 1165 counting only the distinct ones).

The product of its (nonzero) digits is 559872, while the sum is 45.

The spelling of 31398664320 in words is "thirty-one billion, three hundred ninety-eight million, six hundred sixty-four thousand, three hundred twenty".