221120400 has 120 divisors (see below), whose sum is σ = 715599040. Its totient is φ = 58360320.

The previous prime is 221120371. The next prime is 221120401. The reversal of 221120400 is 4021122.

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (12).

It is not an unprimeable number, because it can be changed into a prime (221120401) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 122706 + ... + 124494.

Almost surely, 2^221120400 is an apocalyptic number.

221120400 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 221120400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (357799520).

221120400 is an abundant number, since it is smaller than the sum of its proper divisors (494478640).

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

221120400 is a wasteful number, since it uses less digits than its factorization.

221120400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1913 (or 1902 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 12.

The square root of 221120400 is about 14870.1176861516. The cubic root of 221120400 is about 604.7041332751.

Adding to 221120400 its reverse (4021122), we get a palindrome (225141522).

The spelling of 221120400 in words is "two hundred twenty-one million, one hundred twenty thousand, four hundred".