1311332381 has 2 divisors, whose sum is σ = 1311332382. Its totient is φ = 1311332380.

The previous prime is 1311332377. The next prime is 1311332453. The reversal of 1311332381 is 1832331131.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1302127225 + 9205156 = 36085^2 + 3034^2 .

It is a cyclic number.

It is not a de Polignac number, because 1311332381 - 2² = 1311332377 is a prime.

It is a super-2 number, since 2×1311332381² = 3439185226918258322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1311332381.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1311032381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 655666190 + 655666191.

It is an arithmetic number, because the mean of its divisors is an integer number (655666191).

Almost surely, 2^1311332381 is an apocalyptic number.

It is an amenable number.

1311332381 is a deficient number, since it is larger than the sum of its proper divisors (1).

1311332381 is an equidigital number, since it uses as much as digits as its factorization.

1311332381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1296, while the sum is 26.

The square root of 1311332381 is about 36212.3236067502. The cubic root of 1311332381 is about 1094.5550150108. Note that the first 3 decimals are identical.

The spelling of 1311332381 in words is "one billion, three hundred eleven million, three hundred thirty-two thousand, three hundred eighty-one".