28356431 has 8 divisors (see below), whose sum is σ = 28972944. Its totient is φ = 27743040.

The previous prime is 28356421. The next prime is 28356437. The reversal of 28356431 is 13465382.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28356431 is a prime.

It is a super-2 number, since 2×28356431² = 1608174358115522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28356437) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29795 + ... + 30731.

It is an arithmetic number, because the mean of its divisors is an integer number (3621618).

Almost surely, 2^28356431 is an apocalyptic number.

28356431 is a deficient number, since it is larger than the sum of its proper divisors (616513).

28356431 is an equidigital number, since it uses as much as digits as its factorization.

28356431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1561.

The product of its digits is 17280, while the sum is 32.

The square root of 28356431 is about 5325.0756802134. The cubic root of 28356431 is about 304.9419615446.

The spelling of 28356431 in words is "twenty-eight million, three hundred fifty-six thousand, four hundred thirty-one".