21126704880 has 80 divisors (see below), whose sum is σ = 66104947584. Its totient is φ = 5581128960.

The previous prime is 21126704861. The next prime is 21126704909. The reversal of 21126704880 is 8840762112.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 385666 + ... + 437025.

Almost surely, 2^21126704880 is an apocalyptic number.

21126704880 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21126704880 is an abundant number, since it is smaller than the sum of its proper divisors (44978242704).

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

21126704880 is a wasteful number, since it uses less digits than its factorization.

21126704880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 822814 (or 822808 counting only the distinct ones).

The product of its (nonzero) digits is 43008, while the sum is 39.

The spelling of 21126704880 in words is "twenty-one billion, one hundred twenty-six million, seven hundred four thousand, eight hundred eighty".