1311212131 has 4 divisors (see below), whose sum is σ = 1311291000. Its totient is φ = 1311133264.

The previous prime is 1311212117. The next prime is 1311212137. The reversal of 1311212131 is 1312121131.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 1311212131 - 2⁵ = 1311212099 is a prime.

It is a super-2 number, since 2×1311212131² = 3438554504963122322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1311212137) 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, 3706 + ... + 51343.

It is an arithmetic number, because the mean of its divisors is an integer number (327822750).

Almost surely, 2^1311212131 is an apocalyptic number.

1311212131 is a deficient number, since it is larger than the sum of its proper divisors (78869).

1311212131 is an equidigital number, since it uses as much as digits as its factorization.

1311212131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78868.

The product of its digits is 36, while the sum is 16.

The square root of 1311212131 is about 36210.6632223162. The cubic root of 1311212131 is about 1094.5215568614.

Adding to 1311212131 its reverse (1312121131), we get a palindrome (2623333262).

The spelling of 1311212131 in words is "one billion, three hundred eleven million, two hundred twelve thousand, one hundred thirty-one".