21138351058944 has 2912 divisors, whose sum is σ = 84158837084160. Its totient is φ = 5159780352000.

The previous prime is 21138351058879. The next prime is 21138351059017. The reversal of 21138351058944 is 44985015383112.

21138351058944 is a `hidden beast` number, since 2 + 1 + 1 + 3 + 8 + 3 + 5 + 10 + 589 + 44 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 223 ways as a sum of consecutive naturals, for example, 209290604494 + ... + 209290604594.

Almost surely, 2^{21138351058944} is an apocalyptic number.

21138351058944 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 21138351058944, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42079418542080).

21138351058944 is an abundant number, since it is smaller than the sum of its proper divisors (63020486025216).

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

21138351058944 is a wasteful number, since it uses less digits than its factorization.

21138351058944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 217 (or 180 counting only the distinct ones).

The product of its (nonzero) digits is 4147200, while the sum is 54.

The spelling of 21138351058944 in words is "twenty-one trillion, one hundred thirty-eight billion, three hundred fifty-one million, fifty-eight thousand, nine hundred forty-four".