28523431 has 2 divisors, whose sum is σ = 28523432. Its totient is φ = 28523430.

The previous prime is 28523423. The next prime is 28523461. The reversal of 28523431 is 13432582.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28523431 - 2³ = 28523423 is a prime.

It is a super-2 number, since 2×28523431² = 1627172232023522, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 28523431.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28523461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14261715 + 14261716.

It is an arithmetic number, because the mean of its divisors is an integer number (14261716).

Almost surely, 2^28523431 is an apocalyptic number.

28523431 is a deficient number, since it is larger than the sum of its proper divisors (1).

28523431 is an equidigital number, since it uses as much as digits as its factorization.

28523431 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5760, while the sum is 28.

The square root of 28523431 is about 5340.7331893664. The cubic root of 28523431 is about 305.5394234470.

It can be divided in two parts, 285 and 23431, that added together give a square (23716 = 154²).

The spelling of 28523431 in words is "twenty-eight million, five hundred twenty-three thousand, four hundred thirty-one".