1221434011331 has 2 divisors, whose sum is σ = 1221434011332. Its totient is φ = 1221434011330.

The previous prime is 1221434011297. The next prime is 1221434011333. The reversal of 1221434011331 is 1331104341221.

It is a strong prime.

It is an emirp because it is prime and its reverse (1331104341221) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1221434011331 is a prime.

It is a super-3 number, since 3×1221434011331³ (a number of 37 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

Together with 1221434011333, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1221434011331.

It is not a weakly prime, because it can be changed into another prime (1221434011333) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610717005665 + 610717005666.

It is an arithmetic number, because the mean of its divisors is an integer number (610717005666).

Almost surely, 2^{1221434011331} is an apocalyptic number.

1221434011331 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221434011331 is an equidigital number, since it uses as much as digits as its factorization.

1221434011331 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1728, while the sum is 26.

Adding to 1221434011331 its reverse (1331104341221), we get a palindrome (2552538352552).

The spelling of 1221434011331 in words is "one trillion, two hundred twenty-one billion, four hundred thirty-four million, eleven thousand, three hundred thirty-one".