21790959293 has 2 divisors, whose sum is σ = 21790959294. Its totient is φ = 21790959292.

The previous prime is 21790959241. The next prime is 21790959313. The reversal of 21790959293 is 39295909712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12552289369 + 9238669924 = 112037^2 + 96118^2 .

It is a cyclic number.

It is not a de Polignac number, because 21790959293 - 2¹⁴ = 21790942909 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21790959493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10895479646 + 10895479647.

It is an arithmetic number, because the mean of its divisors is an integer number (10895479647).

Almost surely, 2^21790959293 is an apocalyptic number.

It is an amenable number.

21790959293 is a deficient number, since it is larger than the sum of its proper divisors (1).

21790959293 is an equidigital number, since it uses as much as digits as its factorization.

21790959293 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2755620, while the sum is 56.

The spelling of 21790959293 in words is "twenty-one billion, seven hundred ninety million, nine hundred fifty-nine thousand, two hundred ninety-three".