28969909 has 2 divisors, whose sum is σ = 28969910. Its totient is φ = 28969908.

The previous prime is 28969901. The next prime is 28969933. The reversal of 28969909 is 90996982.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 26728900 + 2241009 = 5170^2 + 1497^2 .

It is a cyclic number.

It is not a de Polignac number, because 28969909 - 2³ = 28969901 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28969901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14484954 + 14484955.

It is an arithmetic number, because the mean of its divisors is an integer number (14484955).

Almost surely, 2^28969909 is an apocalyptic number.

It is an amenable number.

28969909 is a deficient number, since it is larger than the sum of its proper divisors (1).

28969909 is an equidigital number, since it uses as much as digits as its factorization.

28969909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 629856, while the sum is 52.

The square root of 28969909 is about 5382.3702028010. The cubic root of 28969909 is about 307.1253824769.

The spelling of 28969909 in words is "twenty-eight million, nine hundred sixty-nine thousand, nine hundred nine".