221401231400 has 96 divisors (see below), whose sum is σ = 520391525400. Its totient is φ = 87593088000.

The previous prime is 221401231379. The next prime is 221401231411. The reversal of 221401231400 is 4132104122.

It can be written as a sum of positive squares in 12 ways, for example, as 20656013284 + 200745218116 = 143722^2 + 448046^2 .

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 23 ways as a sum of consecutive naturals, for example, 21588674 + ... + 21598926.

Almost surely, 2^221401231400 is an apocalyptic number.

221401231400 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 221401231400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (260195762700).

221401231400 is an abundant number, since it is smaller than the sum of its proper divisors (298990294000).

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

221401231400 is a wasteful number, since it uses less digits than its factorization.

221401231400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11439 (or 11430 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 221401231400 its reverse (4132104122), we get a palindrome (225533335522).

The spelling of 221401231400 in words is "two hundred twenty-one billion, four hundred one million, two hundred thirty-one thousand, four hundred".