221421203312400 has 720 divisors, whose sum is σ = 965014928841600. Its totient is φ = 46717437312000.

The previous prime is 221421203312389. The next prime is 221421203312411. The reversal of 221421203312400 is 4213302124122.

221421203312400 is a `hidden beast` number, since 2 + 2 + 1 + 4 + 21 + 203 + 31 + 2 + 400 = 666.

It is an interprime number because it is at equal distance from previous prime (221421203312389) and next prime (221421203312411).

It is a tau number, because it is divible by the number of its divisors (720).

It is a super-2 number, since 2×221421203312400² (a number of 29 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 9155575 + ... + 22949225.

It is an arithmetic number, because the mean of its divisors is an integer number (1340298512280).

Almost surely, 2^{221421203312400} is an apocalyptic number.

221421203312400 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 221421203312400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (482507464420800).

221421203312400 is an abundant number, since it is smaller than the sum of its proper divisors (743593725529200).

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

221421203312400 is a wasteful number, since it uses less digits than its factorization.

221421203312400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13793709 (or 13793681 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 27.

Adding to 221421203312400 its reverse (4213302124122), we get a palindrome (225634505436522).

The spelling of 221421203312400 in words is "two hundred twenty-one trillion, four hundred twenty-one billion, two hundred three million, three hundred twelve thousand, four hundred".