21765531300 has 72 divisors (see below), whose sum is σ = 63081650016. Its totient is φ = 5794306560.

The previous prime is 21765531287. The next prime is 21765531343. The reversal of 21765531300 is 313556712.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 116727 + ... + 239073.

It is an arithmetic number, because the mean of its divisors is an integer number (876134028).

Almost surely, 2^21765531300 is an apocalyptic number.

21765531300 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 21765531300, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31540825008).

21765531300 is an abundant number, since it is smaller than the sum of its proper divisors (41316118716).

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

21765531300 is a wasteful number, since it uses less digits than its factorization.

21765531300 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122957 (or 122950 counting only the distinct ones).

The product of its (nonzero) digits is 18900, while the sum is 33.

The spelling of 21765531300 in words is "twenty-one billion, seven hundred sixty-five million, five hundred thirty-one thousand, three hundred".