20999999999904 has 96 divisors (see below), whose sum is σ = 55278944280000. Its totient is φ = 6980457222144.

The previous prime is 20999999999893. The next prime is 20999999999987. The reversal of 20999999999904 is 40999999999902.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (96).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 257157672 + ... + 257239320.

It is an arithmetic number, because the mean of its divisors is an integer number (575822336250).

Almost surely, 2^{20999999999904} is an apocalyptic number.

20999999999904 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

20999999999904 is an abundant number, since it is smaller than the sum of its proper divisors (34278944280096).

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

20999999999904 is a wasteful number, since it uses less digits than its factorization.

20999999999904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89110 (or 89102 counting only the distinct ones).

The product of its (nonzero) digits is 27894275208, while the sum is 96.

The spelling of 20999999999904 in words is "twenty trillion, nine hundred ninety-nine billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred four".