21307099939 has 12 divisors (see below), whose sum is σ = 21700380184. Its totient is φ = 20916175104.

The previous prime is 21307099867. The next prime is 21307099951. The reversal of 21307099939 is 93999070312.

It is not a de Polignac number, because 21307099939 - 2¹⁹ = 21306575651 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21307099739) 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, 24861999 + ... + 24862855.

Almost surely, 2^21307099939 is an apocalyptic number.

21307099939 is a deficient number, since it is larger than the sum of its proper divisors (393280245).

21307099939 is an frugal number, since it uses more digits than its factorization.

21307099939 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2214 (or 1357 counting only the distinct ones).

The product of its (nonzero) digits is 826686, while the sum is 52.

The spelling of 21307099939 in words is "twenty-one billion, three hundred seven million, ninety-nine thousand, nine hundred thirty-nine".