131516381 has 2 divisors, whose sum is σ = 131516382. Its totient is φ = 131516380.

The previous prime is 131516339. The next prime is 131516401. The reversal of 131516381 is 183615131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 129163225 + 2353156 = 11365^2 + 1534^2 .

It is a cyclic number.

It is not a de Polignac number, because 131516381 - 2¹⁸ = 131254237 is a prime.

It is a super-2 number, since 2×131516381² = 34593116942674322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131516321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65758190 + 65758191.

It is an arithmetic number, because the mean of its divisors is an integer number (65758191).

Almost surely, 2^131516381 is an apocalyptic number.

It is an amenable number.

131516381 is a deficient number, since it is larger than the sum of its proper divisors (1).

131516381 is an equidigital number, since it uses as much as digits as its factorization.

131516381 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2160, while the sum is 29.

The square root of 131516381 is about 11468.0591644794. The cubic root of 131516381 is about 508.5417539203.

The spelling of 131516381 in words is "one hundred thirty-one million, five hundred sixteen thousand, three hundred eighty-one".