28168631 has 2 divisors, whose sum is σ = 28168632. Its totient is φ = 28168630.

The previous prime is 28168627. The next prime is 28168633. The reversal of 28168631 is 13686182.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28168631 - 2² = 28168627 is a prime.

It is a super-2 number, since 2×28168631² = 1586943544828322, which contains 22 as substring.

Together with 28168633, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 28168591 and 28168600.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28168633) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14084315 + 14084316.

It is an arithmetic number, because the mean of its divisors is an integer number (14084316).

Almost surely, 2^28168631 is an apocalyptic number.

28168631 is a deficient number, since it is larger than the sum of its proper divisors (1).

28168631 is an equidigital number, since it uses as much as digits as its factorization.

28168631 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13824, while the sum is 35.

The square root of 28168631 is about 5307.4128348942. The cubic root of 28168631 is about 304.2672763399.

The spelling of 28168631 in words is "twenty-eight million, one hundred sixty-eight thousand, six hundred thirty-one".