21179023 has 2 divisors, whose sum is σ = 21179024. Its totient is φ = 21179022.

The previous prime is 21179003. The next prime is 21179033. The reversal of 21179023 is 32097112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21179023 - 2⁹ = 21178511 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21179003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10589511 + 10589512.

It is an arithmetic number, because the mean of its divisors is an integer number (10589512).

Almost surely, 2^21179023 is an apocalyptic number.

21179023 is a deficient number, since it is larger than the sum of its proper divisors (1).

21179023 is an equidigital number, since it uses as much as digits as its factorization.

21179023 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 756, while the sum is 25.

The square root of 21179023 is about 4602.0672528767. The cubic root of 21179023 is about 276.6741858572.

The spelling of 21179023 in words is "twenty-one million, one hundred seventy-nine thousand, twenty-three".