31728812 has 6 divisors (see below), whose sum is σ = 55525428. Its totient is φ = 15864404.

The previous prime is 31728811. The next prime is 31728857. The reversal of 31728812 is 21882713.

It is not an unprimeable number, because it can be changed into a prime (31728811) 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 as a sum of consecutive naturals, namely, 3966098 + ... + 3966105.

It is an arithmetic number, because the mean of its divisors is an integer number (9254238).

Almost surely, 2^31728812 is an apocalyptic number.

It is an amenable number.

31728812 is a deficient number, since it is larger than the sum of its proper divisors (23796616).

31728812 is a wasteful number, since it uses less digits than its factorization.

31728812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7932207 (or 7932205 counting only the distinct ones).

The product of its digits is 5376, while the sum is 32.

The square root of 31728812 is about 5632.8333900445. The cubic root of 31728812 is about 316.5808230223.

The spelling of 31728812 in words is "thirty-one million, seven hundred twenty-eight thousand, eight hundred twelve".