28750369 has 6 divisors (see below), whose sum is σ = 29549814. Its totient is φ = 27972000.

The previous prime is 28750321. The next prime is 28750411. The reversal of 28750369 is 96305782.

It can be written as a sum of positive squares in 3 ways, for example, as 11833600 + 16916769 = 3440^2 + 4113^2 .

It is not a de Polignac number, because 28750369 - 2⁹ = 28749857 is a prime.

It is a super-2 number, since 2×28750369² = 1653167435272322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28750769) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9132 + ... + 11869.

It is an arithmetic number, because the mean of its divisors is an integer number (4924969).

Almost surely, 2^28750369 is an apocalyptic number.

It is an amenable number.

28750369 is a deficient number, since it is larger than the sum of its proper divisors (799445).

28750369 is an equidigital number, since it uses as much as digits as its factorization.

28750369 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21075 (or 21038 counting only the distinct ones).

The product of its (nonzero) digits is 90720, while the sum is 40.

The square root of 28750369 is about 5361.9370566988. The cubic root of 28750369 is about 306.3475943851.

The spelling of 28750369 in words is "twenty-eight million, seven hundred fifty thousand, three hundred sixty-nine".