28229969 has 2 divisors, whose sum is σ = 28229970. Its totient is φ = 28229968.

The previous prime is 28229923. The next prime is 28229983. The reversal of 28229969 is 96992282.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 22202944 + 6027025 = 4712^2 + 2455^2 .

It is a cyclic number.

It is not a de Polignac number, because 28229969 - 2²⁰ = 27181393 is a prime.

It is a super-2 number, since 2×28229969² = 1593862299481922, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (28229909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14114984 + 14114985.

It is an arithmetic number, because the mean of its divisors is an integer number (14114985).

Almost surely, 2^28229969 is an apocalyptic number.

It is an amenable number.

28229969 is a deficient number, since it is larger than the sum of its proper divisors (1).

28229969 is an equidigital number, since it uses as much as digits as its factorization.

28229969 is an evil number, because the sum of its binary digits is even.

The product of its digits is 279936, while the sum is 47.

The square root of 28229969 is about 5313.1882142458. The cubic root of 28229969 is about 304.4879664644.

The spelling of 28229969 in words is "twenty-eight million, two hundred twenty-nine thousand, nine hundred sixty-nine".