28669909 has 4 divisors (see below), whose sum is σ = 28693216. Its totient is φ = 28646604.

The previous prime is 28669897. The next prime is 28669919. The reversal of 28669909 is 90996682.

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 a cyclic number.

It is not a de Polignac number, because 28669909 - 2⁵ = 28669877 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28669919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9699 + ... + 12304.

It is an arithmetic number, because the mean of its divisors is an integer number (7173304).

Almost surely, 2^28669909 is an apocalyptic number.

It is an amenable number.

28669909 is a deficient number, since it is larger than the sum of its proper divisors (23307).

28669909 is a wasteful number, since it uses less digits than its factorization.

28669909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23306.

The product of its (nonzero) digits is 419904, while the sum is 49.

The square root of 28669909 is about 5354.4289144595. The cubic root of 28669909 is about 306.0615486998.

The spelling of 28669909 in words is "twenty-eight million, six hundred sixty-nine thousand, nine hundred nine".