21639224799 has 6 divisors (see below), whose sum is σ = 31256658056. Its totient is φ = 14426149860.

The previous prime is 21639224797. The next prime is 21639224813. The reversal of 21639224799 is 99742293612.

21639224799 is a `hidden beast` number, since 2 + 1 + 6 + 392 + 247 + 9 + 9 = 666.

It is not a de Polignac number, because 21639224799 - 2¹ = 21639224797 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21639224797) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1202179147 + ... + 1202179164.

Almost surely, 2^21639224799 is an apocalyptic number.

21639224799 is a deficient number, since it is larger than the sum of its proper divisors (9617433257).

21639224799 is a wasteful number, since it uses less digits than its factorization.

21639224799 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2404358317 (or 2404358314 counting only the distinct ones).

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

The spelling of 21639224799 in words is "twenty-one billion, six hundred thirty-nine million, two hundred twenty-four thousand, seven hundred ninety-nine".