21946499 has 2 divisors, whose sum is σ = 21946500. Its totient is φ = 21946498.

The previous prime is 21946493. The next prime is 21946517. The reversal of 21946499 is 99464912.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21946499 - 2²⁰ = 20897923 is a prime.

It is not a weakly prime, because it can be changed into another prime (21946493) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10973249 + 10973250.

It is an arithmetic number, because the mean of its divisors is an integer number (10973250).

Almost surely, 2^21946499 is an apocalyptic number.

21946499 is a deficient number, since it is larger than the sum of its proper divisors (1).

21946499 is an equidigital number, since it uses as much as digits as its factorization.

21946499 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 139968, while the sum is 44.

The square root of 21946499 is about 4684.7090624712. The cubic root of 21946499 is about 279.9766094406.

The spelling of 21946499 in words is "twenty-one million, nine hundred forty-six thousand, four hundred ninety-nine".