26666021 has 2 divisors, whose sum is σ = 26666022. Its totient is φ = 26666020.

The previous prime is 26665999. The next prime is 26666027. The reversal of 26666021 is 12066662.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21996100 + 4669921 = 4690^2 + 2161^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-26666021 is a prime.

It is a super-2 number, since 2×26666021² = 1422153351944882, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26666027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13333010 + 13333011.

It is an arithmetic number, because the mean of its divisors is an integer number (13333011).

Almost surely, 2^26666021 is an apocalyptic number.

It is an amenable number.

26666021 is a deficient number, since it is larger than the sum of its proper divisors (1).

26666021 is an equidigital number, since it uses as much as digits as its factorization.

26666021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5184, while the sum is 29.

The square root of 26666021 is about 5163.9152781586. The cubic root of 26666021 is about 298.7579051730.

The spelling of 26666021 in words is "twenty-six million, six hundred sixty-six thousand, twenty-one".