26209921 has 2 divisors, whose sum is σ = 26209922. Its totient is φ = 26209920.

The previous prime is 26209913. The next prime is 26209927. The reversal of 26209921 is 12990262.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16974400 + 9235521 = 4120^2 + 3039^2 .

It is a cyclic number.

It is not a de Polignac number, because 26209921 - 2³ = 26209913 is a prime.

It is not a weakly prime, because it can be changed into another prime (26209927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13104960 + 13104961.

It is an arithmetic number, because the mean of its divisors is an integer number (13104961).

Almost surely, 2^26209921 is an apocalyptic number.

It is an amenable number.

26209921 is a deficient number, since it is larger than the sum of its proper divisors (1).

26209921 is an equidigital number, since it uses as much as digits as its factorization.

26209921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3888, while the sum is 31.

The square root of 26209921 is about 5119.5625789710. The cubic root of 26209921 is about 297.0447657056.

The spelling of 26209921 in words is "twenty-six million, two hundred nine thousand, nine hundred twenty-one".