21999999999904 has 48 divisors (see below), whose sum is σ = 44515795503816. Its totient is φ = 10694838067200.

The previous prime is 21999999999863. The next prime is 21999999999917. The reversal of 21999999999904 is 40999999999912.

It can be written as a sum of positive squares in 4 ways, for example, as 13117811909904 + 8882188090000 = 3621852^2 + 2980300^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21999999999797 and 21999999999806.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 5214837 + ... + 8437684.

Almost surely, 2^{21999999999904} is an apocalyptic number.

It is an amenable number.

21999999999904 is an abundant number, since it is smaller than the sum of its proper divisors (22515795503912).

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

21999999999904 is a wasteful number, since it uses less digits than its factorization.

21999999999904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13653929 (or 13653921 counting only the distinct ones).

The product of its (nonzero) digits is 27894275208, while the sum is 97.

The spelling of 21999999999904 in words is "twenty-one trillion, nine hundred ninety-nine billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred four".