221434312221 has 20 divisors (see below), whose sum is σ = 331657418400. Its totient is φ = 147233348136.

The previous prime is 221434312213. The next prime is 221434312241. The reversal of 221434312221 is 122213434122.

221434312221 is a `hidden beast` number, since 2 + 2 + 1 + 4 + 3 + 431 + 2 + 221 = 666.

It is not a de Polignac number, because 221434312221 - 2³ = 221434312213 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221434312241) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 3575841 + ... + 3637238.

It is an arithmetic number, because the mean of its divisors is an integer number (16582870920).

Almost surely, 2^221434312221 is an apocalyptic number.

It is an amenable number.

221434312221 is a deficient number, since it is larger than the sum of its proper divisors (110223106179).

221434312221 is an equidigital number, since it uses as much as digits as its factorization.

221434312221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7213470 (or 7213461 counting only the distinct ones).

The product of its digits is 4608, while the sum is 27.

Adding to 221434312221 its reverse (122213434122), we get a palindrome (343647746343).

The spelling of 221434312221 in words is "two hundred twenty-one billion, four hundred thirty-four million, three hundred twelve thousand, two hundred twenty-one".