1311960381 has 4 divisors (see below), whose sum is σ = 1749280512. Its totient is φ = 874640252.

The previous prime is 1311960373. The next prime is 1311960409. The reversal of 1311960381 is 1830691131.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1311960381 - 2³ = 1311960373 is a prime.

It is a super-2 number, since 2×1311960381² = 3442480082627330322, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1311960301) 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, 218660061 + ... + 218660066.

It is an arithmetic number, because the mean of its divisors is an integer number (437320128).

Almost surely, 2^1311960381 is an apocalyptic number.

It is an amenable number.

1311960381 is a deficient number, since it is larger than the sum of its proper divisors (437320131).

1311960381 is an equidigital number, since it uses as much as digits as its factorization.

1311960381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 437320130.

The product of its (nonzero) digits is 3888, while the sum is 33.

The square root of 1311960381 is about 36220.9936500919. The cubic root of 1311960381 is about 1094.7297154044.

The spelling of 1311960381 in words is "one billion, three hundred eleven million, nine hundred sixty thousand, three hundred eighty-one".