21755375532 has 108 divisors (see below), whose sum is σ = 60509384208. Its totient is φ = 6585691200.

The previous prime is 21755375531. The next prime is 21755375549. The reversal of 21755375532 is 23557355712.

21755375532 is a `hidden beast` number, since 2 + 17 + 55 + 37 + 553 + 2 = 666.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (21755375531) by changing a digit.

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 35 ways as a sum of consecutive naturals, for example, 5560657 + ... + 5564567.

It is an arithmetic number, because the mean of its divisors is an integer number (560272076).

Almost surely, 2^21755375532 is an apocalyptic number.

21755375532 is a gapful number since it is divisible by the number (22) 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 21755375532, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30254692104).

21755375532 is an abundant number, since it is smaller than the sum of its proper divisors (38754008676).

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

21755375532 is a wasteful number, since it uses less digits than its factorization.

21755375532 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5220 (or 5204 counting only the distinct ones).

The product of its digits is 1102500, while the sum is 45.

The spelling of 21755375532 in words is "twenty-one billion, seven hundred fifty-five million, three hundred seventy-five thousand, five hundred thirty-two".