31397625 has 80 divisors (see below), whose sum is σ = 67047552. Its totient is φ = 14320800.

The previous prime is 31397621. The next prime is 31397629. The reversal of 31397625 is 52679313.

It is an interprime number because it is at equal distance from previous prime (31397621) and next prime (31397629).

It is not a de Polignac number, because 31397625 - 2² = 31397621 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31397625.

It is not an unprimeable number, because it can be changed into a prime (31397621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 70654 + ... + 71096.

Almost surely, 2^31397625 is an apocalyptic number.

31397625 is a gapful number since it is divisible by the number (35) formed by its first and last digit.

It is an amenable number.

31397625 is an abundant number, since it is smaller than the sum of its proper divisors (35649927).

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

31397625 is an equidigital number, since it uses as much as digits as its factorization.

31397625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 477 (or 458 counting only the distinct ones).

The product of its digits is 34020, while the sum is 36.

The square root of 31397625 is about 5603.3583679790. The cubic root of 31397625 is about 315.4754724198.

The spelling of 31397625 in words is "thirty-one million, three hundred ninety-seven thousand, six hundred twenty-five".