26639421 has 4 divisors (see below), whose sum is σ = 35519232. Its totient is φ = 17759612.

The previous prime is 26639377. The next prime is 26639423. The reversal of 26639421 is 12493662.

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 26639421 - 2⁷ = 26639293 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (26639423) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4439901 + ... + 4439906.

It is an arithmetic number, because the mean of its divisors is an integer number (8879808).

Almost surely, 2^26639421 is an apocalyptic number.

It is an amenable number.

26639421 is a deficient number, since it is larger than the sum of its proper divisors (8879811).

26639421 is an equidigital number, since it uses as much as digits as its factorization.

26639421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8879810.

The product of its digits is 15552, while the sum is 33.

The square root of 26639421 is about 5161.3390704351. The cubic root of 26639421 is about 298.6585327148.

The spelling of 26639421 in words is "twenty-six million, six hundred thirty-nine thousand, four hundred twenty-one".