21751523992044 has 288 divisors, whose sum is σ = 70657221712896. Its totient is φ = 5477198538240.

The previous prime is 21751523991839. The next prime is 21751523992063. The reversal of 21751523992044 is 44029932515712.

21751523992044 is a `hidden beast` number, since 2 + 1 + 7 + 5 + 1 + 523 + 99 + 20 + 4 + 4 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 28027417 + ... + 28793039.

It is an arithmetic number, because the mean of its divisors is an integer number (245337575392).

Almost surely, 2^{21751523992044} 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 21751523992044, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35328610856448).

21751523992044 is an abundant number, since it is smaller than the sum of its proper divisors (48905697720852).

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

21751523992044 is a wasteful number, since it uses less digits than its factorization.

21751523992044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 765965 (or 765960 counting only the distinct ones).

The product of its (nonzero) digits is 5443200, while the sum is 54.

The spelling of 21751523992044 in words is "twenty-one trillion, seven hundred fifty-one billion, five hundred twenty-three million, nine hundred ninety-two thousand, forty-four".