221231130 has 64 divisors (see below), whose sum is σ = 546023808. Its totient is φ = 57335040.

The previous prime is 221231077. The next prime is 221231137. The reversal of 221231130 is 31132122.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (221231137) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 408660 + ... + 409200.

It is an arithmetic number, because the mean of its divisors is an integer number (8531622).

Almost surely, 2^221231130 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221231130, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (273011904).

221231130 is an abundant number, since it is smaller than the sum of its proper divisors (324792678).

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

221231130 is a wasteful number, since it uses less digits than its factorization.

221231130 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 911.

The product of its (nonzero) digits is 72, while the sum is 15.

The square root of 221231130 is about 14873.8404590072. The cubic root of 221231130 is about 604.8050552386.

Adding to 221231130 its reverse (31132122), we get a palindrome (252363252).

The spelling of 221231130 in words is "two hundred twenty-one million, two hundred thirty-one thousand, one hundred thirty".