21099337439 has 2 divisors, whose sum is σ = 21099337440. Its totient is φ = 21099337438.

The previous prime is 21099337409. The next prime is 21099337447. The reversal of 21099337439 is 93473399012.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21099337439 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21099337409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10549668719 + 10549668720.

It is an arithmetic number, because the mean of its divisors is an integer number (10549668720).

Almost surely, 2^21099337439 is an apocalyptic number.

21099337439 is a deficient number, since it is larger than the sum of its proper divisors (1).

21099337439 is an equidigital number, since it uses as much as digits as its factorization.

21099337439 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1102248, while the sum is 50.

The spelling of 21099337439 in words is "twenty-one billion, ninety-nine million, three hundred thirty-seven thousand, four hundred thirty-nine".