28775644 has 12 divisors (see below), whose sum is σ = 50559768. Its totient is φ = 14330000.

The previous prime is 28775597. The next prime is 28775653. The reversal of 28775644 is 44657782.

It is a super-2 number, since 2×28775644² = 1656075375229472, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 28775644.

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, 13327 + ... + 15334.

It is an arithmetic number, because the mean of its divisors is an integer number (4213314).

Almost surely, 2^28775644 is an apocalyptic number.

It is an amenable number.

28775644 is a deficient number, since it is larger than the sum of its proper divisors (21784124).

28775644 is a wasteful number, since it uses less digits than its factorization.

28775644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28916 (or 28914 counting only the distinct ones).

The product of its digits is 376320, while the sum is 43.

The square root of 28775644 is about 5364.2934297072. The cubic root of 28775644 is about 306.4373401036.

The spelling of 28775644 in words is "twenty-eight million, seven hundred seventy-five thousand, six hundred forty-four".