26689931 has 2 divisors, whose sum is σ = 26689932. Its totient is φ = 26689930.

The previous prime is 26689903. The next prime is 26689963. The reversal of 26689931 is 13998662.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-26689931 is a prime.

It is a super-2 number, since 2×26689931² = 1424704833569522, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (26689991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13344965 + 13344966.

It is an arithmetic number, because the mean of its divisors is an integer number (13344966).

Almost surely, 2^26689931 is an apocalyptic number.

26689931 is a deficient number, since it is larger than the sum of its proper divisors (1).

26689931 is an equidigital number, since it uses as much as digits as its factorization.

26689931 is an evil number, because the sum of its binary digits is even.

The product of its digits is 139968, while the sum is 44.

The square root of 26689931 is about 5166.2298632562. The cubic root of 26689931 is about 298.8471719290.

The spelling of 26689931 in words is "twenty-six million, six hundred eighty-nine thousand, nine hundred thirty-one".