26668021 has 2 divisors, whose sum is σ = 26668022. Its totient is φ = 26668020.

The previous prime is 26668007. The next prime is 26668051. The reversal of 26668021 is 12086662.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17757796 + 8910225 = 4214^2 + 2985^2 .

It is a cyclic number.

It is not a de Polignac number, because 26668021 - 2⁵ = 26667989 is a prime.

It is a super-2 number, since 2×26668021² = 1422366688112882, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26668051) 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, 13334010 + 13334011.

It is an arithmetic number, because the mean of its divisors is an integer number (13334011).

Almost surely, 2^26668021 is an apocalyptic number.

It is an amenable number.

26668021 is a deficient number, since it is larger than the sum of its proper divisors (1).

26668021 is an equidigital number, since it uses as much as digits as its factorization.

26668021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6912, while the sum is 31.

The square root of 26668021 is about 5164.1089260394. The cubic root of 26668021 is about 298.7653741147.

The spelling of 26668021 in words is "twenty-six million, six hundred sixty-eight thousand, twenty-one".