26139921 has 4 divisors (see below), whose sum is σ = 34853232. Its totient is φ = 17426612.

The previous prime is 26139899. The next prime is 26139941. The reversal of 26139921 is 12993162.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 26139921 - 2⁵ = 26139889 is a prime.

It is not an unprimeable number, because it can be changed into a prime (26139941) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4356651 + ... + 4356656.

It is an arithmetic number, because the mean of its divisors is an integer number (8713308).

Almost surely, 2^26139921 is an apocalyptic number.

It is an amenable number.

26139921 is a deficient number, since it is larger than the sum of its proper divisors (8713311).

26139921 is an equidigital number, since it uses as much as digits as its factorization.

26139921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8713310.

The product of its digits is 5832, while the sum is 33.

The square root of 26139921 is about 5112.7214866449. The cubic root of 26139921 is about 296.7800863861.

The spelling of 26139921 in words is "twenty-six million, one hundred thirty-nine thousand, nine hundred twenty-one".