31425320 has 32 divisors (see below), whose sum is σ = 72990720. Its totient is φ = 12164160.

The previous prime is 31425319. The next prime is 31425323. The reversal of 31425320 is 2352413.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 31425292 and 31425301.

It is not an unprimeable number, because it can be changed into a prime (31425323) 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, 11432 + ... + 13911.

It is an arithmetic number, because the mean of its divisors is an integer number (2280960).

Almost surely, 2^31425320 is an apocalyptic number.

It is an amenable number.

31425320 is an abundant number, since it is smaller than the sum of its proper divisors (41565400).

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

31425320 is a wasteful number, since it uses less digits than its factorization.

31425320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25385 (or 25381 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 20.

The square root of 31425320 is about 5605.8291090614. The cubic root of 31425320 is about 315.5682026348.

Adding to 31425320 its reverse (2352413), we get a palindrome (33777733).

The spelling of 31425320 in words is "thirty-one million, four hundred twenty-five thousand, three hundred twenty".