31728630 has 32 divisors (see below), whose sum is σ = 80629344. Its totient is φ = 7963136.

The previous prime is 31728611. The next prime is 31728643. The reversal of 31728630 is 3682713.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 30597 + ... + 31616.

It is an arithmetic number, because the mean of its divisors is an integer number (2519667).

Almost surely, 2^31728630 is an apocalyptic number.

31728630 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

31728630 is an abundant number, since it is smaller than the sum of its proper divisors (48900714).

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

31728630 is a wasteful number, since it uses less digits than its factorization.

31728630 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62240.

The product of its (nonzero) digits is 6048, while the sum is 30.

The square root of 31728630 is about 5632.8172347414. The cubic root of 31728630 is about 316.5802177069.

The spelling of 31728630 in words is "thirty-one million, seven hundred twenty-eight thousand, six hundred thirty".