131625209 has 2 divisors, whose sum is σ = 131625210. Its totient is φ = 131625208.

The previous prime is 131625161. The next prime is 131625223. The reversal of 131625209 is 902526131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 117397225 + 14227984 = 10835^2 + 3772^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-131625209 is a prime.

It is a Chen prime.

It is equal to p_7465142 and since 131625209 and 7465142 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (131625289) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65812604 + 65812605.

It is an arithmetic number, because the mean of its divisors is an integer number (65812605).

Almost surely, 2^131625209 is an apocalyptic number.

It is an amenable number.

131625209 is a deficient number, since it is larger than the sum of its proper divisors (1).

131625209 is an equidigital number, since it uses as much as digits as its factorization.

131625209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3240, while the sum is 29.

The square root of 131625209 is about 11472.8030140851. The cubic root of 131625209 is about 508.6819856878.

The spelling of 131625209 in words is "one hundred thirty-one million, six hundred twenty-five thousand, two hundred nine".