20988460656 has 120 divisors (see below), whose sum is σ = 61892288640. Its totient is φ = 6621264000.

The previous prime is 20988460583. The next prime is 20988460657. The reversal of 20988460656 is 65606488902.

It is a happy number.

20988460656 is a `hidden beast` number, since 20 + 9 + 8 + 8 + 4 + 606 + 5 + 6 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20988460657) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3200581 + ... + 3207131.

It is an arithmetic number, because the mean of its divisors is an integer number (515769072).

Almost surely, 2^20988460656 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 20988460656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30946144320).

20988460656 is an abundant number, since it is smaller than the sum of its proper divisors (40903827984).

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

20988460656 is a wasteful number, since it uses less digits than its factorization.

20988460656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7755 (or 7746 counting only the distinct ones).

The product of its (nonzero) digits is 4976640, while the sum is 54.

The spelling of 20988460656 in words is "twenty billion, nine hundred eighty-eight million, four hundred sixty thousand, six hundred fifty-six".