21899956099 has 16 divisors (see below), whose sum is σ = 25453442560. Its totient is φ = 18455325120.

The previous prime is 21899956061. The next prime is 21899956103. The reversal of 21899956099 is 99065999812.

It is a cyclic number.

It is not a de Polignac number, because 21899956099 - 2¹³ = 21899947907 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21899956049) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9042 + ... + 209479.

It is an arithmetic number, because the mean of its divisors is an integer number (1590840160).

Almost surely, 2^21899956099 is an apocalyptic number.

21899956099 is a deficient number, since it is larger than the sum of its proper divisors (3553486461).

21899956099 is a wasteful number, since it uses less digits than its factorization.

21899956099 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 218770.

The product of its (nonzero) digits is 28343520, while the sum is 67.

The spelling of 21899956099 in words is "twenty-one billion, eight hundred ninety-nine million, nine hundred fifty-six thousand, ninety-nine".