166150561 has 2 divisors, whose sum is σ = 166150562. Its totient is φ = 166150560.

The previous prime is 166150559. The next prime is 166150591. The reversal of 166150561 is 165051661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 165920161 + 230400 = 12881^2 + 480^2 .

It is an emirp because it is prime and its reverse (165051661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 166150561 - 2¹ = 166150559 is a prime.

It is a super-2 number, since 2×166150561² = 55212017841229442, which contains 22 as substring.

Together with 166150559, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (166150511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83075280 + 83075281.

It is an arithmetic number, because the mean of its divisors is an integer number (83075281).

Almost surely, 2^166150561 is an apocalyptic number.

It is an amenable number.

166150561 is a deficient number, since it is larger than the sum of its proper divisors (1).

166150561 is an equidigital number, since it uses as much as digits as its factorization.

166150561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5400, while the sum is 31.

The square root of 166150561 is about 12889.9403024219. The cubic root of 166150561 is about 549.7525730049.

The spelling of 166150561 in words is "one hundred sixty-six million, one hundred fifty thousand, five hundred sixty-one".