1221212122331 has 4 divisors (see below), whose sum is σ = 1263322885200. Its totient is φ = 1179101359464.

The previous prime is 1221212122301. The next prime is 1221212122337. The reversal of 1221212122331 is 1332212121221.

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 1221212122331 - 2²² = 1221207928027 is a prime.

It is a super-2 number, since 2×1221212122331² (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 = 1221212122297 and 1221212122306.

It is not an unprimeable number, because it can be changed into a prime (1221212122337) 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, 21055381391 + ... + 21055381448.

It is an arithmetic number, because the mean of its divisors is an integer number (315830721300).

Almost surely, 2^{1221212122331} is an apocalyptic number.

1221212122331 is a deficient number, since it is larger than the sum of its proper divisors (42110762869).

1221212122331 is an equidigital number, since it uses as much as digits as its factorization.

1221212122331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42110762868.

The product of its digits is 576, while the sum is 23.

Adding to 1221212122331 its reverse (1332212121221), we get a palindrome (2553424243552).

The spelling of 1221212122331 in words is "one trillion, two hundred twenty-one billion, two hundred twelve million, one hundred twenty-two thousand, three hundred thirty-one".