221426400 has 288 divisors, whose sum is σ = 797948928. Its totient is φ = 52992000.

The previous prime is 221426371. The next prime is 221426417. The reversal of 221426400 is 4624122.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1466325 + ... + 1466475.

It is an arithmetic number, because the mean of its divisors is an integer number (2770656).

Almost surely, 2^221426400 is an apocalyptic number.

221426400 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 221426400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (398974464).

221426400 is an abundant number, since it is smaller than the sum of its proper divisors (576522528).

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

221426400 is a wasteful number, since it uses less digits than its factorization.

221426400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 234 (or 221 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 21.

The square root of 221426400 is about 14880.4032203432. The cubic root of 221426400 is about 604.9829469501.

The spelling of 221426400 in words is "two hundred twenty-one million, four hundred twenty-six thousand, four hundred".