131699989 has 2 divisors, whose sum is σ = 131699990. Its totient is φ = 131699988.

The previous prime is 131699947. The next prime is 131699999. The reversal of 131699989 is 989996131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 111133764 + 20566225 = 10542^2 + 4535^2 .

It is an emirp because it is prime and its reverse (989996131) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 131699989 - 2²⁵ = 98145557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131699999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65849994 + 65849995.

It is an arithmetic number, because the mean of its divisors is an integer number (65849995).

Almost surely, 2^131699989 is an apocalyptic number.

It is an amenable number.

131699989 is a deficient number, since it is larger than the sum of its proper divisors (1).

131699989 is an equidigital number, since it uses as much as digits as its factorization.

131699989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 944784, while the sum is 55.

The square root of 131699989 is about 11476.0615630973. The cubic root of 131699989 is about 508.7782996531.

The spelling of 131699989 in words is "one hundred thirty-one million, six hundred ninety-nine thousand, nine hundred eighty-nine".