31520425 has 12 divisors (see below), whose sum is σ = 39824460. Its totient is φ = 24739520.

The previous prime is 31520417. The next prime is 31520453. The reversal of 31520425 is 52402513.

It can be written as a sum of positive squares in 6 ways, for example, as 1281424 + 30239001 = 1132^2 + 5499^2 .

It is not a de Polignac number, because 31520425 - 2³ = 31520417 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31520396 and 31520405.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10570 + ... + 13219.

It is an arithmetic number, because the mean of its divisors is an integer number (3318705).

Almost surely, 2^31520425 is an apocalyptic number.

It is an amenable number.

31520425 is a deficient number, since it is larger than the sum of its proper divisors (8304035).

31520425 is a wasteful number, since it uses less digits than its factorization.

31520425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23852 (or 23847 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 22.

The square root of 31520425 is about 5614.3053889150. The cubic root of 31520425 is about 315.8862252641.

Adding to 31520425 its reverse (52402513), we get a palindrome (83922938).

The spelling of 31520425 in words is "thirty-one million, five hundred twenty thousand, four hundred twenty-five".