31213628 has 24 divisors (see below), whose sum is σ = 57894480. Its totient is φ = 14698880.

The previous prime is 31213627. The next prime is 31213643. The reversal of 31213628 is 82631213.

It is a junction number, because it is equal to n+sod(n) for n = 31213597 and 31213606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31213627) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1475 + ... + 8037.

It is an arithmetic number, because the mean of its divisors is an integer number (2412270).

Almost surely, 2^31213628 is an apocalyptic number.

It is an amenable number.

31213628 is a deficient number, since it is larger than the sum of its proper divisors (26680852).

31213628 is a wasteful number, since it uses less digits than its factorization.

31213628 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6637 (or 6635 counting only the distinct ones).

The product of its digits is 1728, while the sum is 26.

The square root of 31213628 is about 5586.9157860129. The cubic root of 31213628 is about 314.8580127700.

The spelling of 31213628 in words is "thirty-one million, two hundred thirteen thousand, six hundred twenty-eight".