28015931 has 2 divisors, whose sum is σ = 28015932. Its totient is φ = 28015930.

The previous prime is 28015927. The next prime is 28015957. The reversal of 28015931 is 13951082.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28015931 - 2² = 28015927 is a prime.

It is a super-2 number, since 2×28015931² = 1569784779593522, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 28015894 and 28015903.

It is not a weakly prime, because it can be changed into another prime (28015921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14007965 + 14007966.

It is an arithmetic number, because the mean of its divisors is an integer number (14007966).

Almost surely, 2^28015931 is an apocalyptic number.

28015931 is a deficient number, since it is larger than the sum of its proper divisors (1).

28015931 is an equidigital number, since it uses as much as digits as its factorization.

28015931 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2160, while the sum is 29.

The square root of 28015931 is about 5293.0077460741. The cubic root of 28015931 is about 303.7164766246.

The spelling of 28015931 in words is "twenty-eight million, fifteen thousand, nine hundred thirty-one".