221430121 has 24 divisors (see below), whose sum is σ = 249529280. Its totient is φ = 196305120.

The previous prime is 221430107. The next prime is 221430133. The reversal of 221430121 is 121034122.

It is not a de Polignac number, because 221430121 - 2⁹ = 221429609 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 221430095 and 221430104.

It is not an unprimeable number, because it can be changed into a prime (221430721) 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 23 ways as a sum of consecutive naturals, for example, 1358386 + ... + 1358548.

Almost surely, 2^221430121 is an apocalyptic number.

It is an amenable number.

221430121 is a deficient number, since it is larger than the sum of its proper divisors (28099159).

221430121 is a wasteful number, since it uses less digits than its factorization.

221430121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 397 (or 386 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 221430121 is about 14880.5282500320. The cubic root of 221430121 is about 604.9863357795.

Adding to 221430121 its reverse (121034122), we get a palindrome (342464243).

The spelling of 221430121 in words is "two hundred twenty-one million, four hundred thirty thousand, one hundred twenty-one".