1213188131 has 4 divisors (see below), whose sum is σ = 1252323264. Its totient is φ = 1174053000.

The previous prime is 1213188101. The next prime is 1213188143. The reversal of 1213188131 is 1318813121.

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 1213188131 - 2²⁶ = 1146079267 is a prime.

It is a super-2 number, since 2×1213188131² = 2943650882398546322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1213188094 and 1213188103.

It is not an unprimeable number, because it can be changed into a prime (1213188101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19567520 + ... + 19567581.

It is an arithmetic number, because the mean of its divisors is an integer number (313080816).

Almost surely, 2^1213188131 is an apocalyptic number.

1213188131 is a deficient number, since it is larger than the sum of its proper divisors (39135133).

1213188131 is an equidigital number, since it uses as much as digits as its factorization.

1213188131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39135132.

The product of its digits is 1152, while the sum is 29.

The square root of 1213188131 is about 34830.8502767303. The cubic root of 1213188131 is about 1066.5373056773.

The spelling of 1213188131 in words is "one billion, two hundred thirteen million, one hundred eighty-eight thousand, one hundred thirty-one".