21765480044 has 96 divisors (see below), whose sum is σ = 47974381056. Its totient is φ = 8393748480.

The previous prime is 21765480031. The next prime is 21765480073. The reversal of 21765480044 is 44008456712.

It is a super-2 number, since 2×21765480044² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21765479983 and 21765480010.

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 31 ways as a sum of consecutive naturals, for example, 13492982 + ... + 13494594.

It is an arithmetic number, because the mean of its divisors is an integer number (499733136).

Almost surely, 2^21765480044 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 21765480044, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23987190528).

21765480044 is an abundant number, since it is smaller than the sum of its proper divisors (26208901012).

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

21765480044 is a wasteful number, since it uses less digits than its factorization.

21765480044 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2055 (or 2053 counting only the distinct ones).

The product of its (nonzero) digits is 215040, while the sum is 41.

The spelling of 21765480044 in words is "twenty-one billion, seven hundred sixty-five million, four hundred eighty thousand, forty-four".