28569890 has 32 divisors (see below), whose sum is σ = 53187840. Its totient is φ = 11042944.

The previous prime is 28569889. The next prime is 28569913. The reversal of 28569890 is 9896582.

It is a super-2 number, since 2×28569890² = 1632477229224200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (47).

It is a Curzon number.

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 15 ways as a sum of consecutive naturals, for example, 41489 + ... + 42171.

It is an arithmetic number, because the mean of its divisors is an integer number (1662120).

Almost surely, 2^28569890 is an apocalyptic number.

28569890 is a deficient number, since it is larger than the sum of its proper divisors (24617950).

28569890 is a wasteful number, since it uses less digits than its factorization.

28569890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 826.

The product of its (nonzero) digits is 311040, while the sum is 47.

The square root of 28569890 is about 5345.0809161321. The cubic root of 28569890 is about 305.7052211272.

The spelling of 28569890 in words is "twenty-eight million, five hundred sixty-nine thousand, eight hundred ninety".