28745389 has 2 divisors, whose sum is σ = 28745390. Its totient is φ = 28745388.

The previous prime is 28745363. The next prime is 28745393. The reversal of 28745389 is 98354782.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 24157225 + 4588164 = 4915^2 + 2142^2 .

It is a cyclic number.

It is not a de Polignac number, because 28745389 - 2⁵ = 28745357 is a prime.

It is a super-2 number, since 2×28745389² = 1652594777522642, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28745329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14372694 + 14372695.

It is an arithmetic number, because the mean of its divisors is an integer number (14372695).

Almost surely, 2^28745389 is an apocalyptic number.

It is an amenable number.

28745389 is a deficient number, since it is larger than the sum of its proper divisors (1).

28745389 is an equidigital number, since it uses as much as digits as its factorization.

28745389 is an evil number, because the sum of its binary digits is even.

The product of its digits is 483840, while the sum is 46.

The square root of 28745389 is about 5361.4726521731. The cubic root of 28745389 is about 306.3299053471.

The spelling of 28745389 in words is "twenty-eight million, seven hundred forty-five thousand, three hundred eighty-nine".