20021009976 has 128 divisors (see below), whose sum is σ = 61524748800. Its totient is φ = 5981472000.

The previous prime is 20021009923. The next prime is 20021009999. The reversal of 20021009976 is 67990012002.

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

It is a self number, because there is not a number n which added to its sum of digits gives 20021009976.

It is a congruent number.

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, 109356 + ... + 228036.

It is an arithmetic number, because the mean of its divisors is an integer number (480662100).

Almost surely, 2^20021009976 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 20021009976, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30762374400).

20021009976 is an abundant number, since it is smaller than the sum of its proper divisors (41503738824).

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

20021009976 is a wasteful number, since it uses less digits than its factorization.

20021009976 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118778 (or 118768 counting only the distinct ones).

The product of its (nonzero) digits is 13608, while the sum is 36.

The spelling of 20021009976 in words is "twenty billion, twenty-one million, nine thousand, nine hundred seventy-six".