21099180708 has 36 divisors (see below), whose sum is σ = 53338535068. Its totient is φ = 7032467520.

The previous prime is 21099180701. The next prime is 21099180721. The reversal of 21099180708 is 80708199012.

It can be written as a sum of positive squares in 2 ways, for example, as 5685461604 + 15413719104 = 75402^2 + 124152^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is not an unprimeable number, because it can be changed into a prime (21099180701) 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 11 ways as a sum of consecutive naturals, for example, 698478 + ... + 728058.

Almost surely, 2^21099180708 is an apocalyptic number.

It is an amenable number.

21099180708 is an abundant number, since it is smaller than the sum of its proper divisors (32239354360).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21099180708 is a wasteful number, since it uses less digits than its factorization.

21099180708 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49404 (or 49399 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 45.

The spelling of 21099180708 in words is "twenty-one billion, ninety-nine million, one hundred eighty thousand, seven hundred eight".