28569639 has 32 divisors (see below), whose sum is σ = 46725120. Its totient is φ = 15155712.

The previous prime is 28569637. The next prime is 28569641. The reversal of 28569639 is 93696582.

It is an interprime number because it is at equal distance from previous prime (28569637) and next prime (28569641).

It is not a de Polignac number, because 28569639 - 2¹ = 28569637 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28569637) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 27697 + ... + 28709.

It is an arithmetic number, because the mean of its divisors is an integer number (1460160).

Almost surely, 2^28569639 is an apocalyptic number.

28569639 is a deficient number, since it is larger than the sum of its proper divisors (18155481).

28569639 is a wasteful number, since it uses less digits than its factorization.

28569639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1119.

The product of its digits is 699840, while the sum is 48.

The square root of 28569639 is about 5345.0574365483. The cubic root of 28569639 is about 305.7043258695.

The spelling of 28569639 in words is "twenty-eight million, five hundred sixty-nine thousand, six hundred thirty-nine".