28813969 has 2 divisors, whose sum is σ = 28813970. Its totient is φ = 28813968.

The previous prime is 28813957. The next prime is 28813979. The reversal of 28813969 is 96931882.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16703569 + 12110400 = 4087^2 + 3480^2 .

It is a cyclic number.

It is not a de Polignac number, because 28813969 - 2¹¹ = 28811921 is a prime.

It is a super-2 number, since 2×28813969² = 1660489619065922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (28813909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14406984 + 14406985.

It is an arithmetic number, because the mean of its divisors is an integer number (14406985).

Almost surely, 2^28813969 is an apocalyptic number.

It is an amenable number.

28813969 is a deficient number, since it is larger than the sum of its proper divisors (1).

28813969 is an equidigital number, since it uses as much as digits as its factorization.

28813969 is an evil number, because the sum of its binary digits is even.

The product of its digits is 186624, while the sum is 46.

The square root of 28813969 is about 5367.8644729538. The cubic root of 28813969 is about 306.5733231715.

The spelling of 28813969 in words is "twenty-eight million, eight hundred thirteen thousand, nine hundred sixty-nine".