26664643 has 2 divisors, whose sum is σ = 26664644. Its totient is φ = 26664642.

The previous prime is 26664641. The next prime is 26664683. The reversal of 26664643 is 34646662.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 26664643 - 2¹ = 26664641 is a prime.

It is a super-2 number, since 2×26664643² = 1422006372634898, which contains 22 as substring.

Together with 26664641, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (26664641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13332321 + 13332322.

It is an arithmetic number, because the mean of its divisors is an integer number (13332322).

Almost surely, 2^26664643 is an apocalyptic number.

26664643 is a deficient number, since it is larger than the sum of its proper divisors (1).

26664643 is an equidigital number, since it uses as much as digits as its factorization.

26664643 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 124416, while the sum is 37.

The square root of 26664643 is about 5163.7818505433. The cubic root of 26664643 is about 298.7527588548.

The spelling of 26664643 in words is "twenty-six million, six hundred sixty-four thousand, six hundred forty-three".