21820264317908 has 48 divisors (see below), whose sum is σ = 44826060384000. Its totient is φ = 9289611021600.

The previous prime is 21820264317871. The next prime is 21820264317913. The reversal of 21820264317908 is 80971346202812.

It is a super-2 number, since 2×21820264317908² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21820264317908.

It is a congruent number.

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, 52455023 + ... + 52869366.

It is an arithmetic number, because the mean of its divisors is an integer number (933876258000).

Almost surely, 2^{21820264317908} is an apocalyptic number.

21820264317908 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21820264317908 is an abundant number, since it is smaller than the sum of its proper divisors (23005796066092).

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

21820264317908 is a wasteful number, since it uses less digits than its factorization.

21820264317908 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105324565 (or 105324549 counting only the distinct ones).

The product of its (nonzero) digits is 2322432, while the sum is 53.

The spelling of 21820264317908 in words is "twenty-one trillion, eight hundred twenty billion, two hundred sixty-four million, three hundred seventeen thousand, nine hundred eight".