31201132320 has 72 divisors (see below), whose sum is σ = 106473868956. Its totient is φ = 8320301568.

The previous prime is 31201132301. The next prime is 31201132327. The reversal of 31201132320 is 2323110213.

31201132320 is a `hidden beast` number, since 312 + 0 + 1 + 1 + 32 + 320 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 30935181456 + 265950864 = 175884^2 + 16308^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 31201132293 and 31201132302.

It is not an unprimeable number, because it can be changed into a prime (31201132327) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10832287 + ... + 10835166.

Almost surely, 2^31201132320 is an apocalyptic number.

31201132320 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

31201132320 is an abundant number, since it is smaller than the sum of its proper divisors (75272736636).

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

31201132320 is a wasteful number, since it uses less digits than its factorization.

31201132320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21667474 (or 21667463 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

Adding to 31201132320 its reverse (2323110213), we get a palindrome (33524242533).

The spelling of 31201132320 in words is "thirty-one billion, two hundred one million, one hundred thirty-two thousand, three hundred twenty".