221321230400 has 84 divisors (see below), whose sum is σ = 544681509060. Its totient is φ = 88513382400.

The previous prime is 221321230387. The next prime is 221321230441. The reversal of 221321230400 is 4032123122.

It can be written as a sum of positive squares in 6 ways, for example, as 40022403136 + 181298827264 = 200056^2 + 425792^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17255990 + ... + 17268810.

Almost surely, 2^221321230400 is an apocalyptic number.

221321230400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221321230400 is an abundant number, since it is smaller than the sum of its proper divisors (323360278660).

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

221321230400 is a wasteful number, since it uses less digits than its factorization.

221321230400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23632 (or 23617 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

Adding to 221321230400 its reverse (4032123122), we get a palindrome (225353353522).

The spelling of 221321230400 in words is "two hundred twenty-one billion, three hundred twenty-one million, two hundred thirty thousand, four hundred".