21211079 has 2 divisors, whose sum is σ = 21211080. Its totient is φ = 21211078.

The previous prime is 21211039. The next prime is 21211109. The reversal of 21211079 is 97011212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21211079 - 2⁸ = 21210823 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21211009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10605539 + 10605540.

It is an arithmetic number, because the mean of its divisors is an integer number (10605540).

Almost surely, 2^21211079 is an apocalyptic number.

21211079 is a deficient number, since it is larger than the sum of its proper divisors (1).

21211079 is an equidigital number, since it uses as much as digits as its factorization.

21211079 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 252, while the sum is 23.

The square root of 21211079 is about 4605.5487186653. The cubic root of 21211079 is about 276.8137043609.

The spelling of 21211079 in words is "twenty-one million, two hundred eleven thousand, seventy-nine".