21837838464 has 384 divisors, whose sum is σ = 71575358400. Its totient is φ = 6586085376.

The previous prime is 21837838457. The next prime is 21837838489. The reversal of 21837838464 is 46483873812.

21837838464 is a `hidden beast` number, since 2 + 1 + 83 + 78 + 38 + 464 = 666.

It is a tau number, because it is divible by the number of its divisors (384).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 21837838464.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 21430147 + ... + 21431165.

Almost surely, 2^21837838464 is an apocalyptic number.

21837838464 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 21837838464, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35787679200).

21837838464 is an abundant number, since it is smaller than the sum of its proper divisors (49737519936).

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

21837838464 is a wasteful number, since it uses less digits than its factorization.

21837838464 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1114 (or 1090 counting only the distinct ones).

The product of its digits is 6193152, while the sum is 54.

The spelling of 21837838464 in words is "twenty-one billion, eight hundred thirty-seven million, eight hundred thirty-eight thousand, four hundred sixty-four".