31216628 has 24 divisors (see below), whose sum is σ = 57329664. Its totient is φ = 14853600.

The previous prime is 31216609. The next prime is 31216631. The reversal of 31216628 is 82661213.

It is a Smith number, since the sum of its digits (29) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 31216628.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5501 + ... + 9627.

It is an arithmetic number, because the mean of its divisors is an integer number (2388736).

Almost surely, 2^31216628 is an apocalyptic number.

It is an amenable number.

31216628 is a deficient number, since it is larger than the sum of its proper divisors (26113036).

31216628 is a wasteful number, since it uses less digits than its factorization.

31216628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4223 (or 4221 counting only the distinct ones).

The product of its digits is 3456, while the sum is 29.

The square root of 31216628 is about 5587.1842640099. The cubic root of 31216628 is about 314.8680996438.

The spelling of 31216628 in words is "thirty-one million, two hundred sixteen thousand, six hundred twenty-eight".