1221322312031 has 4 divisors (see below), whose sum is σ = 1293164800992. Its totient is φ = 1149479823072.

The previous prime is 1221322311991. The next prime is 1221322312051. The reversal of 1221322312031 is 1302132231221.

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 1221322312031 - 2¹⁰ = 1221322311007 is a prime.

It is a super-2 number, since 2×1221322312031² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1221322311988 and 1221322312006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221322312051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35921244455 + ... + 35921244488.

It is an arithmetic number, because the mean of its divisors is an integer number (323291200248).

Almost surely, 2^{1221322312031} is an apocalyptic number.

1221322312031 is a deficient number, since it is larger than the sum of its proper divisors (71842488961).

1221322312031 is an equidigital number, since it uses as much as digits as its factorization.

1221322312031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71842488960.

The product of its (nonzero) digits is 864, while the sum is 23.

Adding to 1221322312031 its reverse (1302132231221), we get a palindrome (2523454543252).

The spelling of 1221322312031 in words is "one trillion, two hundred twenty-one billion, three hundred twenty-two million, three hundred twelve thousand, thirty-one".