31728856 has 16 divisors (see below), whose sum is σ = 60161400. Its totient is φ = 15685824.

The previous prime is 31728811. The next prime is 31728857. The reversal of 31728856 is 65882713.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31728857) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21570 + ... + 22993.

Almost surely, 2^31728856 is an apocalyptic number.

It is an amenable number.

31728856 is a deficient number, since it is larger than the sum of its proper divisors (28432544).

31728856 is a wasteful number, since it uses less digits than its factorization.

31728856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44658 (or 44654 counting only the distinct ones).

The product of its digits is 80640, while the sum is 40.

The square root of 31728856 is about 5632.8372957152. The cubic root of 31728856 is about 316.5809693620.

The spelling of 31728856 in words is "thirty-one million, seven hundred twenty-eight thousand, eight hundred fifty-six".