21957723412768 has 144 divisors (see below), whose sum is σ = 51078163502016. Its totient is φ = 9210814878720.

The previous prime is 21957723412673. The next prime is 21957723412771. The reversal of 21957723412768 is 86721432775912.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 260098821 + ... + 260183227.

It is an arithmetic number, because the mean of its divisors is an integer number (354709468764).

Almost surely, 2^{21957723412768} 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 21957723412768, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25539081751008).

21957723412768 is an abundant number, since it is smaller than the sum of its proper divisors (29120440089248).

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

21957723412768 is a wasteful number, since it uses less digits than its factorization.

21957723412768 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88827 (or 88806 counting only the distinct ones).

The product of its digits is 71124480, while the sum is 64.

The spelling of 21957723412768 in words is "twenty-one trillion, nine hundred fifty-seven billion, seven hundred twenty-three million, four hundred twelve thousand, seven hundred sixty-eight".