21109877376 has 256 divisors, whose sum is σ = 66213504000. Its totient is φ = 5955640320.

The previous prime is 21109877357. The next prime is 21109877429. The reversal of 21109877376 is 67377890112.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10931131 + ... + 10933061.

It is an arithmetic number, because the mean of its divisors is an integer number (258646500).

Almost surely, 2^21109877376 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 21109877376, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33106752000).

21109877376 is an abundant number, since it is smaller than the sum of its proper divisors (45103626624).

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

21109877376 is an equidigital number, since it uses as much as digits as its factorization.

21109877376 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2052 (or 2026 counting only the distinct ones).

The product of its (nonzero) digits is 889056, while the sum is 51.

The spelling of 21109877376 in words is "twenty-one billion, one hundred nine million, eight hundred seventy-seven thousand, three hundred seventy-six".