21274579 has 2 divisors, whose sum is σ = 21274580. Its totient is φ = 21274578.

The previous prime is 21274553. The next prime is 21274607. The reversal of 21274579 is 97547212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21274579 - 2⁹ = 21274067 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21274529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10637289 + 10637290.

It is an arithmetic number, because the mean of its divisors is an integer number (10637290).

Almost surely, 2^21274579 is an apocalyptic number.

21274579 is a deficient number, since it is larger than the sum of its proper divisors (1).

21274579 is an equidigital number, since it uses as much as digits as its factorization.

21274579 is an evil number, because the sum of its binary digits is even.

The product of its digits is 35280, while the sum is 37.

The square root of 21274579 is about 4612.4374250498. The cubic root of 21274579 is about 277.0896632671.

The spelling of 21274579 in words is "twenty-one million, two hundred seventy-four thousand, five hundred seventy-nine".