21051419187800 has 96 divisors (see below), whose sum is σ = 50097781393920. Its totient is φ = 8224379049600.

The previous prime is 21051419187719. The next prime is 21051419187809. The reversal of 21051419187800 is 878191415012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21051419187809) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5408144 + ... + 8446943.

It is an arithmetic number, because the mean of its divisors is an integer number (521851889520).

Almost surely, 2^{21051419187800} is an apocalyptic number.

21051419187800 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21051419187800 is an abundant number, since it is smaller than the sum of its proper divisors (29046362206120).

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

21051419187800 is a wasteful number, since it uses less digits than its factorization.

21051419187800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13855281 (or 13855272 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 47.

The spelling of 21051419187800 in words is "twenty-one trillion, fifty-one billion, four hundred nineteen million, one hundred eighty-seven thousand, eight hundred".