31728860 has 24 divisors (see below), whose sum is σ = 70138320. Its totient is φ = 12023424.

The previous prime is 31728857. The next prime is 31728863. The reversal of 31728860 is 6882713.

It is an interprime number because it is at equal distance from previous prime (31728857) and next prime (31728863).

It is a self number, because there is not a number n which added to its sum of digits gives 31728860.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31728863) 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, 41369 + ... + 42128.

It is an arithmetic number, because the mean of its divisors is an integer number (2922430).

Almost surely, 2^31728860 is an apocalyptic number.

It is an amenable number.

31728860 is an abundant number, since it is smaller than the sum of its proper divisors (38409460).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31728860 is a wasteful number, since it uses less digits than its factorization.

31728860 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83525 (or 83523 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 35.

The square root of 31728860 is about 5632.8376507760. The cubic root of 31728860 is about 316.5809826656.

The spelling of 31728860 in words is "thirty-one million, seven hundred twenty-eight thousand, eight hundred sixty".