26491631 has 2 divisors, whose sum is σ = 26491632. Its totient is φ = 26491630.

The previous prime is 26491613. The next prime is 26491637. The reversal of 26491631 is 13619462.

Together with previous prime (26491613) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-26491631 is a prime.

It is a super-2 number, since 2×26491631² = 1403613026080322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26491637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13245815 + 13245816.

It is an arithmetic number, because the mean of its divisors is an integer number (13245816).

Almost surely, 2^26491631 is an apocalyptic number.

26491631 is a deficient number, since it is larger than the sum of its proper divisors (1).

26491631 is an equidigital number, since it uses as much as digits as its factorization.

26491631 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7776, while the sum is 32.

The square root of 26491631 is about 5147.0021371668. The cubic root of 26491631 is about 298.1052096118.

The spelling of 26491631 in words is "twenty-six million, four hundred ninety-one thousand, six hundred thirty-one".