31628225 has 6 divisors (see below), whose sum is σ = 39219030. Its totient is φ = 25302560.

The previous prime is 31628173. The next prime is 31628239. The reversal of 31628225 is 52282613.

It can be written as a sum of positive squares in 3 ways, for example, as 7579009 + 24049216 = 2753^2 + 4904^2 .

It is not a de Polignac number, because 31628225 - 2⁶ = 31628161 is a prime.

It is an unprimeable number.

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 5 ways as a sum of consecutive naturals, for example, 632540 + ... + 632589.

It is an arithmetic number, because the mean of its divisors is an integer number (6536505).

Almost surely, 2^31628225 is an apocalyptic number.

It is an amenable number.

31628225 is a deficient number, since it is larger than the sum of its proper divisors (7590805).

31628225 is a wasteful number, since it uses less digits than its factorization.

31628225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1265139 (or 1265134 counting only the distinct ones).

The product of its digits is 5760, while the sum is 29.

The square root of 31628225 is about 5623.8976697660. The cubic root of 31628225 is about 316.2459263016.

The spelling of 31628225 in words is "thirty-one million, six hundred twenty-eight thousand, two hundred twenty-five".