28905669 has 24 divisors (see below), whose sum is σ = 47334560. Its totient is φ = 16850592.

The previous prime is 28905659. The next prime is 28905677. The reversal of 28905669 is 96650982.

28905669 is a `hidden beast` number, since 2 + 89 + 0 + 566 + 9 = 666.

It is not a de Polignac number, because 28905669 - 2⁵ = 28905637 is a prime.

It is a super-2 number, since 2×28905669² = 1671075400675122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28905629) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4279 + ... + 8724.

Almost surely, 2^28905669 is an apocalyptic number.

It is an amenable number.

28905669 is a deficient number, since it is larger than the sum of its proper divisors (18428891).

28905669 is a wasteful number, since it uses less digits than its factorization.

28905669 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13041 (or 13038 counting only the distinct ones).

The product of its (nonzero) digits is 233280, while the sum is 45.

The square root of 28905669 is about 5376.3992597276. The cubic root of 28905669 is about 306.8982003578.

The spelling of 28905669 in words is "twenty-eight million, nine hundred five thousand, six hundred sixty-nine".