28909569 has 16 divisors (see below), whose sum is σ = 41739264. Its totient is φ = 17692800.

The previous prime is 28909541. The next prime is 28909579. The reversal of 28909569 is 96590982.

It is not a de Polignac number, because 28909569 - 2⁹ = 28909057 is a prime.

It is a super-2 number, since 2×28909569² = 1671526359531522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28909519) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5509 + ... + 9389.

It is an arithmetic number, because the mean of its divisors is an integer number (2608704).

It is a Proth number, since it is equal to 3529 ⋅ 2¹³ + 1 and 3529 < 2¹³.

Almost surely, 2^28909569 is an apocalyptic number.

It is an amenable number.

28909569 is a deficient number, since it is larger than the sum of its proper divisors (12829695).

28909569 is a wasteful number, since it uses less digits than its factorization.

28909569 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4088.

The product of its (nonzero) digits is 349920, while the sum is 48.

The square root of 28909569 is about 5376.7619437725. The cubic root of 28909569 is about 306.9120021390.

The spelling of 28909569 in words is "twenty-eight million, nine hundred nine thousand, five hundred sixty-nine".