221213311231 has 4 divisors (see below), whose sum is σ = 241323612264. Its totient is φ = 201103010200.

The previous prime is 221213311229. The next prime is 221213311307. The reversal of 221213311231 is 132113312122.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 221213311231 - 2¹ = 221213311229 is a prime.

It is a super-2 number, since 2×221213311231² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221213311831) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10055150500 + ... + 10055150521.

It is an arithmetic number, because the mean of its divisors is an integer number (60330903066).

Almost surely, 2^221213311231 is an apocalyptic number.

221213311231 is a deficient number, since it is larger than the sum of its proper divisors (20110301033).

221213311231 is a wasteful number, since it uses less digits than its factorization.

221213311231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20110301032.

The product of its digits is 432, while the sum is 22.

Adding to 221213311231 its reverse (132113312122), we get a palindrome (353326623353).

The spelling of 221213311231 in words is "two hundred twenty-one billion, two hundred thirteen million, three hundred eleven thousand, two hundred thirty-one".