221323431400 has 96 divisors (see below), whose sum is σ = 533173687200. Its totient is φ = 85386579200.

The previous prime is 221323431391. The next prime is 221323431457. The reversal of 221323431400 is 4134323122.

It is a super-2 number, since 2×221323431400² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (25).

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, 448455 + ... + 802345.

It is an arithmetic number, because the mean of its divisors is an integer number (5553892575).

Almost surely, 2^221323431400 is an apocalyptic number.

221323431400 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 221323431400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (266586843600).

221323431400 is an abundant number, since it is smaller than the sum of its proper divisors (311850255800).

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

221323431400 is a wasteful number, since it uses less digits than its factorization.

221323431400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 354019 (or 354010 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 25.

Adding to 221323431400 its reverse (4134323122), we get a palindrome (225457754522).

The spelling of 221323431400 in words is "two hundred twenty-one billion, three hundred twenty-three million, four hundred thirty-one thousand, four hundred".