21022138368 has 756 divisors, whose sum is σ = 80559732708. Its totient is φ = 5222891520.

The previous prime is 21022138363. The next prime is 21022138601. The reversal of 21022138368 is 86383122012.

21022138368 is a `hidden beast` number, since 210 + 2 + 2 + 1 + 383 + 68 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21022138363) by changing a digit.

It is a polite number, since it can be written in 53 ways as a sum of consecutive naturals, for example, 914006005 + ... + 914006027.

It is an arithmetic number, because the mean of its divisors is an integer number (106560493).

Almost surely, 2^21022138368 is an apocalyptic number.

21022138368 is a gapful number since it is divisible by the number (28) 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 21022138368, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40279866354).

21022138368 is an abundant number, since it is smaller than the sum of its proper divisors (59537594340).

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

21022138368 is a wasteful number, since it uses less digits than its factorization.

21022138368 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103 (or 46 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The spelling of 21022138368 in words is "twenty-one billion, twenty-two million, one hundred thirty-eight thousand, three hundred sixty-eight".