21807840912 has 160 divisors (see below), whose sum is σ = 66329088000. Its totient is φ = 6086914560.

The previous prime is 21807840871. The next prime is 21807840983. The reversal of 21807840912 is 21904870812.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3421953 + ... + 3428319.

It is an arithmetic number, because the mean of its divisors is an integer number (414556800).

Almost surely, 2^21807840912 is an apocalyptic number.

21807840912 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21807840912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33164544000).

21807840912 is an abundant number, since it is smaller than the sum of its proper divisors (44521247088).

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

21807840912 is a wasteful number, since it uses less digits than its factorization.

21807840912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6901 (or 6895 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 42.

The spelling of 21807840912 in words is "twenty-one billion, eight hundred seven million, eight hundred forty thousand, nine hundred twelve".