221320121231 has 12 divisors (see below), whose sum is σ = 243287147376. Its totient is φ = 201185286720.

The previous prime is 221320121161. The next prime is 221320121233. The reversal of 221320121231 is 132121023122.

It is a de Polignac number, because none of the positive numbers 2^k-221320121231 is a prime.

It is a super-2 number, since 2×221320121231² (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 (221320121233) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1793150 + ... + 1912596.

It is an arithmetic number, because the mean of its divisors is an integer number (20273928948).

Almost surely, 2^221320121231 is an apocalyptic number.

221320121231 is a deficient number, since it is larger than the sum of its proper divisors (21967026145).

221320121231 is a wasteful number, since it uses less digits than its factorization.

221320121231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134782 (or 134771 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 20.

Adding to 221320121231 its reverse (132121023122), we get a palindrome (353441144353).

The spelling of 221320121231 in words is "two hundred twenty-one billion, three hundred twenty million, one hundred twenty-one thousand, two hundred thirty-one".