28979409 has 4 divisors (see below), whose sum is σ = 38639216. Its totient is φ = 19319604.

The previous prime is 28979383. The next prime is 28979411. The reversal of 28979409 is 90497982.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 28979409 - 2¹⁵ = 28946641 is a prime.

It is a super-2 number, since 2×28979409² = 1679612291978562, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28979459) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4829899 + ... + 4829904.

It is an arithmetic number, because the mean of its divisors is an integer number (9659804).

Almost surely, 2^28979409 is an apocalyptic number.

It is an amenable number.

28979409 is a deficient number, since it is larger than the sum of its proper divisors (9659807).

28979409 is an equidigital number, since it uses as much as digits as its factorization.

28979409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9659806.

The product of its (nonzero) digits is 326592, while the sum is 48.

The square root of 28979409 is about 5383.2526412941. The cubic root of 28979409 is about 307.1589503221.

The spelling of 28979409 in words is "twenty-eight million, nine hundred seventy-nine thousand, four hundred nine".