21550320099 has 108 divisors (see below), whose sum is σ = 39984923160. Its totient is φ = 11143440000.

The previous prime is 21550320067. The next prime is 21550320109. The reversal of 21550320099 is 99002305512.

It is a happy number.

It is not a de Polignac number, because 21550320099 - 2⁵ = 21550320067 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (21550320059) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 107 ways as a sum of consecutive naturals, for example, 13392807 + ... + 13394415.

It is an arithmetic number, because the mean of its divisors is an integer number (370230770).

Almost surely, 2^21550320099 is an apocalyptic number.

21550320099 is a deficient number, since it is larger than the sum of its proper divisors (18434603061).

21550320099 is a wasteful number, since it uses less digits than its factorization.

21550320099 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1902 (or 1881 counting only the distinct ones).

The product of its (nonzero) digits is 24300, while the sum is 36.

The spelling of 21550320099 in words is "twenty-one billion, five hundred fifty million, three hundred twenty thousand, ninety-nine".