21321029200900 has 243 divisors, whose sum is σ = 55084964455773. Its totient is φ = 7154492716800.

The previous prime is 21321029200873. The next prime is 21321029201023. The reversal of 21321029200900 is 900292012312.

The square root of 21321029200900 is 4617470.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 13 ways, for example, as 21271890725316 + 49138475584 = 4612146^2 + 221672^2 .

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 6602980486 + ... + 6602983714.

Almost surely, 2^{21321029200900} is an apocalyptic number.

21321029200900 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

21321029200900 is the 4617470-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21321029200900

21321029200900 is an abundant number, since it is smaller than the sum of its proper divisors (33763935254873).

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

21321029200900 is a wasteful number, since it uses less digits than its factorization.

21321029200900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6520 (or 3260 counting only the distinct ones).

The product of its (nonzero) digits is 3888, while the sum is 31.

The spelling of 21321029200900 in words is "twenty-one trillion, three hundred twenty-one billion, twenty-nine million, two hundred thousand, nine hundred".