166125121 has 2 divisors, whose sum is σ = 166125122. Its totient is φ = 166125120.

The previous prime is 166125107. The next prime is 166125131. The reversal of 166125121 is 121521661.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 130782096 + 35343025 = 11436^2 + 5945^2 .

It is a cyclic number.

It is not a de Polignac number, because 166125121 - 2⁷ = 166124993 is a prime.

It is not a weakly prime, because it can be changed into another prime (166125131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83062560 + 83062561.

It is an arithmetic number, because the mean of its divisors is an integer number (83062561).

Almost surely, 2^166125121 is an apocalyptic number.

It is an amenable number.

166125121 is a deficient number, since it is larger than the sum of its proper divisors (1).

166125121 is an equidigital number, since it uses as much as digits as its factorization.

166125121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 720, while the sum is 25.

The square root of 166125121 is about 12888.9534485931. The cubic root of 166125121 is about 549.7245132756.

Adding to 166125121 its reverse (121521661), we get a palindrome (287646782).

The spelling of 166125121 in words is "one hundred sixty-six million, one hundred twenty-five thousand, one hundred twenty-one".