1311936381 has 12 divisors (see below), whose sum is σ = 2165736352. Its totient is φ = 749677896.

The previous prime is 1311936371. The next prime is 1311936383. The reversal of 1311936381 is 1836391131.

1311936381 is a `hidden beast` number, since 1 + 3 + 1 + 19 + 3 + 638 + 1 = 666.

It is not a de Polignac number, because 1311936381 - 2⁷ = 1311936253 is a prime.

It is a super-2 number, since 2×1311936381² = 3442354135582754322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1311936383) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10412131 + ... + 10412256.

Almost surely, 2^1311936381 is an apocalyptic number.

It is an amenable number.

1311936381 is a deficient number, since it is larger than the sum of its proper divisors (853799971).

1311936381 is a wasteful number, since it uses less digits than its factorization.

1311936381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20824400 (or 20824397 counting only the distinct ones).

The product of its digits is 11664, while the sum is 36.

The square root of 1311936381 is about 36220.6623489963. The cubic root of 1311936381 is about 1094.7230399809.

The spelling of 1311936381 in words is "one billion, three hundred eleven million, nine hundred thirty-six thousand, three hundred eighty-one".