1213123023131 has 4 divisors (see below), whose sum is σ = 1213126413000. Its totient is φ = 1213119633264.

The previous prime is 1213123023043. The next prime is 1213123023139. The reversal of 1213123023131 is 1313203213121.

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 1213123023131 - 2²² = 1213118828827 is a prime.

It is a super-2 number, since 2×1213123023131² (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 = 1213123023097 and 1213123023106.

It is not an unprimeable number, because it can be changed into a prime (1213123023139) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1084961 + ... + 1898258.

It is an arithmetic number, because the mean of its divisors is an integer number (303281603250).

Almost surely, 2^{1213123023131} is an apocalyptic number.

1213123023131 is a deficient number, since it is larger than the sum of its proper divisors (3389869).

1213123023131 is an equidigital number, since it uses as much as digits as its factorization.

1213123023131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3389868.

The product of its (nonzero) digits is 648, while the sum is 23.

Adding to 1213123023131 its reverse (1313203213121), we get a palindrome (2526326236252).

The spelling of 1213123023131 in words is "one trillion, two hundred thirteen billion, one hundred twenty-three million, twenty-three thousand, one hundred thirty-one".