166550961 has 4 divisors (see below), whose sum is σ = 222067952. Its totient is φ = 111033972.

The previous prime is 166550953. The next prime is 166550971. The reversal of 166550961 is 169055661.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 166550961 - 2³ = 166550953 is a prime.

It is a super-2 number, since 2×166550961² = 55478445220047042, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166550971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27758491 + ... + 27758496.

It is an arithmetic number, because the mean of its divisors is an integer number (55516988).

Almost surely, 2^166550961 is an apocalyptic number.

It is an amenable number.

166550961 is a deficient number, since it is larger than the sum of its proper divisors (55516991).

166550961 is an equidigital number, since it uses as much as digits as its factorization.

166550961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55516990.

The product of its (nonzero) digits is 48600, while the sum is 39.

The square root of 166550961 is about 12905.4624481264. The cubic root of 166550961 is about 550.1938281028.

The spelling of 166550961 in words is "one hundred sixty-six million, five hundred fifty thousand, nine hundred sixty-one".