26215591 has 2 divisors, whose sum is σ = 26215592. Its totient is φ = 26215590.

The previous prime is 26215517. The next prime is 26215601. The reversal of 26215591 is 19551262.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 26215591 - 2⁷ = 26215463 is a prime.

It is a super-2 number, since 2×26215591² = 1374514422958562, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26212591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13107795 + 13107796.

It is an arithmetic number, because the mean of its divisors is an integer number (13107796).

Almost surely, 2^26215591 is an apocalyptic number.

26215591 is a deficient number, since it is larger than the sum of its proper divisors (1).

26215591 is an equidigital number, since it uses as much as digits as its factorization.

26215591 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5400, while the sum is 31.

The square root of 26215591 is about 5120.1163072727. The cubic root of 26215591 is about 297.0661840887.

The spelling of 26215591 in words is "twenty-six million, two hundred fifteen thousand, five hundred ninety-one".