131591566 has 4 divisors (see below), whose sum is σ = 197387352. Its totient is φ = 65795782.

The previous prime is 131591563. The next prime is 131591569. The reversal of 131591566 is 665195131.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (131591563) and next prime (131591569).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131591563) 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, 32897890 + ... + 32897893.

It is an arithmetic number, because the mean of its divisors is an integer number (49346838).

Almost surely, 2^131591566 is an apocalyptic number.

131591566 is a deficient number, since it is larger than the sum of its proper divisors (65795786).

131591566 is an equidigital number, since it uses as much as digits as its factorization.

131591566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65795785.

The product of its digits is 24300, while the sum is 37.

The square root of 131591566 is about 11471.3367137400. The cubic root of 131591566 is about 508.6386428093.

The spelling of 131591566 in words is "one hundred thirty-one million, five hundred ninety-one thousand, five hundred sixty-six".