21837981024 has 120 divisors (see below), whose sum is σ = 64365989688. Its totient is φ = 7263336960.

The previous prime is 21837981007. The next prime is 21837981047. The reversal of 21837981024 is 42018973812.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 1201444 + ... + 1219484.

Almost surely, 2^21837981024 is an apocalyptic number.

21837981024 is a gapful number since it is divisible by the number (24) 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 21837981024, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32182994844).

21837981024 is an abundant number, since it is smaller than the sum of its proper divisors (42528008664).

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

21837981024 is a wasteful number, since it uses less digits than its factorization.

21837981024 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18530 (or 18513 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 45.

The spelling of 21837981024 in words is "twenty-one billion, eight hundred thirty-seven million, nine hundred eighty-one thousand, twenty-four".