21108268776 has 128 divisors (see below), whose sum is σ = 62320066560. Its totient is φ = 5830272000.

The previous prime is 21108268763. The next prime is 21108268829. The reversal of 21108268776 is 67786280112.

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, 7534576 + ... + 7537376.

It is an arithmetic number, because the mean of its divisors is an integer number (486875520).

Almost surely, 2^21108268776 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 21108268776, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31160033280).

21108268776 is an abundant number, since it is smaller than the sum of its proper divisors (41211797784).

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

21108268776 is a wasteful number, since it uses less digits than its factorization.

21108268776 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4295 (or 4291 counting only the distinct ones).

The product of its (nonzero) digits is 451584, while the sum is 48.

The spelling of 21108268776 in words is "twenty-one billion, one hundred eight million, two hundred sixty-eight thousand, seven hundred seventy-six".