21375137757776 has 120 divisors (see below), whose sum is σ = 46156981701600. Its totient is φ = 9581189587200.

The previous prime is 21375137757769. The next prime is 21375137757821. The reversal of 21375137757776 is 67775773157312.

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 23 ways as a sum of consecutive naturals, for example, 44286035 + ... + 44766093.

It is an arithmetic number, because the mean of its divisors is an integer number (384641514180).

Almost surely, 2^{21375137757776} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21375137757776, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23078490850800).

21375137757776 is an abundant number, since it is smaller than the sum of its proper divisors (24781843943824).

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

21375137757776 is a wasteful number, since it uses less digits than its factorization.

21375137757776 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 480409 (or 480392 counting only the distinct ones).

The product of its digits is 317652300, while the sum is 68.

The spelling of 21375137757776 in words is "twenty-one trillion, three hundred seventy-five billion, one hundred thirty-seven million, seven hundred fifty-seven thousand, seven hundred seventy-six".