21986948256 has 384 divisors, whose sum is σ = 75188736000. Its totient is φ = 5467004928.

The previous prime is 21986948213. The next prime is 21986948267. The reversal of 21986948256 is 65284968912.

It is a super-2 number, since 2×21986948256² (a number of 21 digits) contains 22 as substring.

Its product of digits (14929920) is a multiple of the sum of its prime divisors (1620).

It is a self number, because there is not a number n which added to its sum of digits gives 21986948256.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 14666995 + ... + 14668493.

It is an arithmetic number, because the mean of its divisors is an integer number (195804000).

Almost surely, 2^21986948256 is an apocalyptic number.

21986948256 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21986948256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37594368000).

21986948256 is an abundant number, since it is smaller than the sum of its proper divisors (53201787744).

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

21986948256 is a wasteful number, since it uses less digits than its factorization.

21986948256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1628 (or 1620 counting only the distinct ones).

The product of its digits is 14929920, while the sum is 60.

The spelling of 21986948256 in words is "twenty-one billion, nine hundred eighty-six million, nine hundred forty-eight thousand, two hundred fifty-six".