221340402400 has 144 divisors (see below), whose sum is σ = 596106565488. Its totient is φ = 79732224000.

The previous prime is 221340402389. The next prime is 221340402427. The reversal of 221340402400 is 4204043122.

It is a happy number.

It is a congruent number.

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, 166855 + ... + 685945.

It is an arithmetic number, because the mean of its divisors is an integer number (4139628927).

Almost surely, 2^221340402400 is an apocalyptic number.

221340402400 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 221340402400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (298053282744).

221340402400 is an abundant number, since it is smaller than the sum of its proper divisors (374766163088).

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

221340402400 is a wasteful number, since it uses less digits than its factorization.

221340402400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 519165 (or 519152 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 22.

Adding to 221340402400 its reverse (4204043122), we get a palindrome (225544445522).

The spelling of 221340402400 in words is "two hundred twenty-one billion, three hundred forty million, four hundred two thousand, four hundred".