21790959291 has 12 divisors (see below), whose sum is σ = 31483211032. Its totient is φ = 14523899616.

The previous prime is 21790959241. The next prime is 21790959293. The reversal of 21790959291 is 19295909712.

21790959291 is a `hidden beast` number, since 217 + 90 + 9 + 59 + 291 = 666.

It is not a de Polignac number, because 21790959291 - 2⁹ = 21790958779 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21790959293) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 243061 + ... + 320406.

Almost surely, 2^21790959291 is an apocalyptic number.

21790959291 is a deficient number, since it is larger than the sum of its proper divisors (9692251741).

21790959291 is a wasteful number, since it uses less digits than its factorization.

21790959291 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 567770 (or 567767 counting only the distinct ones).

The product of its (nonzero) digits is 918540, while the sum is 54.

The spelling of 21790959291 in words is "twenty-one billion, seven hundred ninety million, nine hundred fifty-nine thousand, two hundred ninety-one".