21976807680 has 576 divisors, whose sum is σ = 81896048640. Its totient is φ = 5573836800.

The previous prime is 21976807651. The next prime is 21976807747. The reversal of 21976807680 is 8670867912.

It is a tau number, because it is divible by the number of its divisors (576).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 78209140 + ... + 78209420.

It is an arithmetic number, because the mean of its divisors is an integer number (142180640).

Almost surely, 2^21976807680 is an apocalyptic number.

21976807680 is a gapful number since it is divisible by the number (20) 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 21976807680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40948024320).

21976807680 is an abundant number, since it is smaller than the sum of its proper divisors (59919240960).

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

21976807680 is a wasteful number, since it uses less digits than its factorization.

21976807680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 415 (or 395 counting only the distinct ones).

The product of its (nonzero) digits is 2032128, while the sum is 54.

The spelling of 21976807680 in words is "twenty-one billion, nine hundred seventy-six million, eight hundred seven thousand, six hundred eighty".