28731644 has 12 divisors (see below), whose sum is σ = 50769264. Its totient is φ = 14226144.

The previous prime is 28731631. The next prime is 28731701. The reversal of 28731644 is 44613782.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34457 + ... + 35280.

It is an arithmetic number, because the mean of its divisors is an integer number (4230772).

Almost surely, 2^28731644 is an apocalyptic number.

It is an amenable number.

28731644 is a deficient number, since it is larger than the sum of its proper divisors (22037620).

28731644 is a wasteful number, since it uses less digits than its factorization.

28731644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69844 (or 69842 counting only the distinct ones).

The product of its digits is 32256, while the sum is 35.

The square root of 28731644 is about 5360.1906682505. The cubic root of 28731644 is about 306.2810722881.

The spelling of 28731644 in words is "twenty-eight million, seven hundred thirty-one thousand, six hundred forty-four".