31123912320 has 384 divisors, whose sum is σ = 109876338000. Its totient is φ = 8116568064.

The previous prime is 31123912297. The next prime is 31123912343. The reversal of 31123912320 is 2321932113.

31123912320 is a `hidden beast` number, since 31 + 12 + 391 + 232 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (31123912297) and next prime (31123912343).

It can be written as a sum of positive squares in 8 ways, for example, as 4887687744 + 26236224576 = 69912^2 + 161976^2 .

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

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, 55877482 + ... + 55878038.

Almost surely, 2^31123912320 is an apocalyptic number.

31123912320 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 31123912320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (54938169000).

31123912320 is an abundant number, since it is smaller than the sum of its proper divisors (78752425680).

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

31123912320 is a wasteful number, since it uses less digits than its factorization.

31123912320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 780 (or 765 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 27.

The spelling of 31123912320 in words is "thirty-one billion, one hundred twenty-three million, nine hundred twelve thousand, three hundred twenty".