21943983499 has 2 divisors, whose sum is σ = 21943983500. Its totient is φ = 21943983498.

The previous prime is 21943983491. The next prime is 21943983541. The reversal of 21943983499 is 99438934912.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21943983499 - 2³ = 21943983491 is a prime.

It is not a weakly prime, because it can be changed into another prime (21943983491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10971991749 + 10971991750.

It is an arithmetic number, because the mean of its divisors is an integer number (10971991750).

Almost surely, 2^21943983499 is an apocalyptic number.

21943983499 is a deficient number, since it is larger than the sum of its proper divisors (1).

21943983499 is an equidigital number, since it uses as much as digits as its factorization.

21943983499 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15116544, while the sum is 61.

The spelling of 21943983499 in words is "twenty-one billion, nine hundred forty-three million, nine hundred eighty-three thousand, four hundred ninety-nine".