28563990 has 64 divisors (see below), whose sum is σ = 84381696. Its totient is φ = 6026112.

The previous prime is 28563959. The next prime is 28564001. The reversal of 28563990 is 9936582.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2502 + ... + 7961.

It is an arithmetic number, because the mean of its divisors is an integer number (1318464).

Almost surely, 2^28563990 is an apocalyptic number.

28563990 is an abundant number, since it is smaller than the sum of its proper divisors (55817706).

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

28563990 is a wasteful number, since it uses less digits than its factorization.

28563990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10493.

The product of its (nonzero) digits is 116640, while the sum is 42.

The square root of 28563990 is about 5344.5289783104. The cubic root of 28563990 is about 305.6841758358.

The spelling of 28563990 in words is "twenty-eight million, five hundred sixty-three thousand, nine hundred ninety".