21546531300 has 144 divisors (see below), whose sum is σ = 71293214720. Its totient is φ = 4921741440.

The previous prime is 21546531283. The next prime is 21546531301. The reversal of 21546531300 is 313564512.

It is a super-2 number, since 2×21546531300² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (21546531301) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5178621 + ... + 5182779.

Almost surely, 2^21546531300 is an apocalyptic number.

21546531300 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 21546531300, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35646607360).

21546531300 is an abundant number, since it is smaller than the sum of its proper divisors (49746683420).

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

21546531300 is a wasteful number, since it uses less digits than its factorization.

21546531300 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6650 (or 6643 counting only the distinct ones).

The product of its (nonzero) digits is 10800, while the sum is 30.

The spelling of 21546531300 in words is "twenty-one billion, five hundred forty-six million, five hundred thirty-one thousand, three hundred".