21875781200 has 120 divisors (see below), whose sum is σ = 64685109888. Its totient is φ = 6923312640.

The previous prime is 21875781181. The next prime is 21875781289. The reversal of 21875781200 is 218757812.

It is a super-2 number, since 2×21875781200² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

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 23 ways as a sum of consecutive naturals, for example, 264092 + ... + 336891.

Almost surely, 2^21875781200 is an apocalyptic number.

21875781200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21875781200 is an abundant number, since it is smaller than the sum of its proper divisors (42809328688).

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

21875781200 is a wasteful number, since it uses less digits than its factorization.

21875781200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 601021 (or 601010 counting only the distinct ones).

The product of its (nonzero) digits is 62720, while the sum is 41.

21875781200 divided by its reverse (218757812) gives a square (100 = 10²).

The spelling of 21875781200 in words is "twenty-one billion, eight hundred seventy-five million, seven hundred eighty-one thousand, two hundred".