31012320 has 48 divisors (see below), whose sum is σ = 97690320. Its totient is φ = 8269824.

The previous prime is 31012309. The next prime is 31012321. The reversal of 31012320 is 2321013.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (48).

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 31012296 and 31012305.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31012321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31825 + ... + 32784.

It is an arithmetic number, because the mean of its divisors is an integer number (2035215).

Almost surely, 2^31012320 is an apocalyptic number.

31012320 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

31012320 is an abundant number, since it is smaller than the sum of its proper divisors (66678000).

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

31012320 is a wasteful number, since it uses less digits than its factorization.

31012320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64627 (or 64619 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 12.

The square root of 31012320 is about 5568.8706215893. The cubic root of 31012320 is about 314.1796745766.

Adding to 31012320 its reverse (2321013), we get a palindrome (33333333).

The spelling of 31012320 in words is "thirty-one million, twelve thousand, three hundred twenty".