21853851400 has 24 divisors (see below), whose sum is σ = 50810204970. Its totient is φ = 8741540480.

The previous prime is 21853851391. The next prime is 21853851401. The reversal of 21853851400 is 415835812.

It can be written as a sum of positive squares in 3 ways, for example, as 15983533476 + 5870317924 = 126426^2 + 76618^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21853851400.

It is not an unprimeable number, because it can be changed into a prime (21853851401) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 54634429 + ... + 54634828.

Almost surely, 2^21853851400 is an apocalyptic number.

21853851400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21853851400 is an abundant number, since it is smaller than the sum of its proper divisors (28956353570).

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

21853851400 is a wasteful number, since it uses less digits than its factorization.

21853851400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109269273 (or 109269264 counting only the distinct ones).

The product of its (nonzero) digits is 38400, while the sum is 37.

The spelling of 21853851400 in words is "twenty-one billion, eight hundred fifty-three million, eight hundred fifty-one thousand, four hundred".