26189921 has 2 divisors, whose sum is σ = 26189922. Its totient is φ = 26189920.

The previous prime is 26189909. The next prime is 26189959. The reversal of 26189921 is 12998162.

It is an a-pointer prime, because the next prime (26189959) can be obtained adding 26189921 to its sum of digits (38).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 26122321 + 67600 = 5111^2 + 260^2 .

It is a cyclic number.

It is not a de Polignac number, because 26189921 - 2¹⁸ = 25927777 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (26189971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13094960 + 13094961.

It is an arithmetic number, because the mean of its divisors is an integer number (13094961).

Almost surely, 2^26189921 is an apocalyptic number.

It is an amenable number.

26189921 is a deficient number, since it is larger than the sum of its proper divisors (1).

26189921 is an equidigital number, since it uses as much as digits as its factorization.

26189921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15552, while the sum is 38.

The square root of 26189921 is about 5117.6089143271. The cubic root of 26189921 is about 296.9691911797.

The spelling of 26189921 in words is "twenty-six million, one hundred eighty-nine thousand, nine hundred twenty-one".