221021130 has 64 divisors (see below), whose sum is σ = 589638528. Its totient is φ = 52565760.

The previous prime is 221021111. The next prime is 221021137. The reversal of 221021130 is 31120122.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (221021137) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 11172 + ... + 23808.

It is an arithmetic number, because the mean of its divisors is an integer number (9213102).

Almost surely, 2^221021130 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221021130, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (294819264).

221021130 is an abundant number, since it is smaller than the sum of its proper divisors (368617398).

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

221021130 is a wasteful number, since it uses less digits than its factorization.

221021130 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12711.

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 221021130 is about 14866.7794091390. The cubic root of 221021130 is about 604.6136275827.

Adding to 221021130 its reverse (31120122), we get a palindrome (252141252).

It can be divided in two parts, 22102 and 1130, that added together give a palindrome (23232).

The spelling of 221021130 in words is "two hundred twenty-one million, twenty-one thousand, one hundred thirty".