31728994 has 8 divisors (see below), whose sum is σ = 51920208. Its totient is φ = 14422260.

The previous prime is 31728979. The next prime is 31728997. The reversal of 31728994 is 49982713.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 31728994.

It is not an unprimeable number, because it can be changed into a prime (31728997) 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, 721092 + ... + 721135.

It is an arithmetic number, because the mean of its divisors is an integer number (6490026).

Almost surely, 2^31728994 is an apocalyptic number.

31728994 is a deficient number, since it is larger than the sum of its proper divisors (20191214).

31728994 is a wasteful number, since it uses less digits than its factorization.

31728994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1442240.

The product of its digits is 108864, while the sum is 43.

The square root of 31728994 is about 5632.8495453012. The cubic root of 31728994 is about 316.5814283355.

The spelling of 31728994 in words is "thirty-one million, seven hundred twenty-eight thousand, nine hundred ninety-four".