131746721 has 2 divisors, whose sum is σ = 131746722. Its totient is φ = 131746720.

The previous prime is 131746717. The next prime is 131746733. The reversal of 131746721 is 127647131.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 126247696 + 5499025 = 11236^2 + 2345^2 .

It is a cyclic number.

It is not a de Polignac number, because 131746721 - 2² = 131746717 is a prime.

It is not a weakly prime, because it can be changed into another prime (131746421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65873360 + 65873361.

It is an arithmetic number, because the mean of its divisors is an integer number (65873361).

Almost surely, 2^131746721 is an apocalyptic number.

It is an amenable number.

131746721 is a deficient number, since it is larger than the sum of its proper divisors (1).

131746721 is an equidigital number, since it uses as much as digits as its factorization.

131746721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7056, while the sum is 32.

The square root of 131746721 is about 11478.0974468768. The cubic root of 131746721 is about 508.8384702879.

The spelling of 131746721 in words is "one hundred thirty-one million, seven hundred forty-six thousand, seven hundred twenty-one".