21436729299 has 12 divisors (see below), whose sum is σ = 32110985816. Its totient is φ = 14291152704.

The previous prime is 21436729283. The next prime is 21436729319. The reversal of 21436729299 is 99292763412.

It is not a de Polignac number, because 21436729299 - 2⁴ = 21436729283 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21436799299) 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, 44108254 + ... + 44108739.

Almost surely, 2^21436729299 is an apocalyptic number.

21436729299 is a deficient number, since it is larger than the sum of its proper divisors (10674256517).

21436729299 is an frugal number, since it uses more digits than its factorization.

21436729299 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88217008 (or 88216996 counting only the distinct ones).

The product of its digits is 2939328, while the sum is 54.

The spelling of 21436729299 in words is "twenty-one billion, four hundred thirty-six million, seven hundred twenty-nine thousand, two hundred ninety-nine".