28756644 has 24 divisors (see below), whose sum is σ = 76684608. Its totient is φ = 8216160.

The previous prime is 28756631. The next prime is 28756657. The reversal of 28756644 is 44665782.

It is an interprime number because it is at equal distance from previous prime (28756631) and next prime (28756657).

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 28756596 and 28756605.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 171087 + ... + 171254.

It is an arithmetic number, because the mean of its divisors is an integer number (3195192).

Almost surely, 2^28756644 is an apocalyptic number.

It is an amenable number.

28756644 is an abundant number, since it is smaller than the sum of its proper divisors (47927964).

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

28756644 is a wasteful number, since it uses less digits than its factorization.

28756644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 342355 (or 342353 counting only the distinct ones).

The product of its digits is 322560, while the sum is 42.

The square root of 28756644 is about 5362.5221677863. The cubic root of 28756644 is about 306.3698803752.

The spelling of 28756644 in words is "twenty-eight million, seven hundred fifty-six thousand, six hundred forty-four".