166542461 has 2 divisors, whose sum is σ = 166542462. Its totient is φ = 166542460.

The previous prime is 166542449. The next prime is 166542463. The reversal of 166542461 is 164245661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 89208025 + 77334436 = 9445^2 + 8794^2 .

It is a cyclic number.

It is not a de Polignac number, because 166542461 - 2²² = 162348157 is a prime.

Together with 166542463, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166542463) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83271230 + 83271231.

It is an arithmetic number, because the mean of its divisors is an integer number (83271231).

Almost surely, 2^166542461 is an apocalyptic number.

It is an amenable number.

166542461 is a deficient number, since it is larger than the sum of its proper divisors (1).

166542461 is an equidigital number, since it uses as much as digits as its factorization.

166542461 is an evil number, because the sum of its binary digits is even.

The product of its digits is 34560, while the sum is 35.

The square root of 166542461 is about 12905.1331260084. The cubic root of 166542461 is about 550.1844681506.

The spelling of 166542461 in words is "one hundred sixty-six million, five hundred forty-two thousand, four hundred sixty-one".