1213555551331 has 2 divisors, whose sum is σ = 1213555551332. Its totient is φ = 1213555551330.

The previous prime is 1213555551283. The next prime is 1213555551353. The reversal of 1213555551331 is 1331555553121.

It is a strong prime.

It is an emirp because it is prime and its reverse (1331555553121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1213555551331 - 2⁹ = 1213555550819 is a prime.

It is a super-2 number, since 2×1213555551331² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1213555551431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 606777775665 + 606777775666.

It is an arithmetic number, because the mean of its divisors is an integer number (606777775666).

Almost surely, 2^{1213555551331} is an apocalyptic number.

1213555551331 is a deficient number, since it is larger than the sum of its proper divisors (1).

1213555551331 is an equidigital number, since it uses as much as digits as its factorization.

1213555551331 is an evil number, because the sum of its binary digits is even.

The product of its digits is 168750, while the sum is 40.

The spelling of 1213555551331 in words is "one trillion, two hundred thirteen billion, five hundred fifty-five million, five hundred fifty-one thousand, three hundred thirty-one".