21149767799 has 2 divisors, whose sum is σ = 21149767800. Its totient is φ = 21149767798.

The previous prime is 21149767721. The next prime is 21149767811. The reversal of 21149767799 is 99776794112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21149767799 - 2²⁸ = 20881332343 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21149767399) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10574883899 + 10574883900.

It is an arithmetic number, because the mean of its divisors is an integer number (10574883900).

Almost surely, 2^21149767799 is an apocalyptic number.

21149767799 is a deficient number, since it is larger than the sum of its proper divisors (1).

21149767799 is an equidigital number, since it uses as much as digits as its factorization.

21149767799 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12002256, while the sum is 62.

The spelling of 21149767799 in words is "twenty-one billion, one hundred forty-nine million, seven hundred sixty-seven thousand, seven hundred ninety-nine".