165226661 has 4 divisors (see below), whose sum is σ = 165261900. Its totient is φ = 165191424.

The previous prime is 165226657. The next prime is 165226681. The reversal of 165226661 is 166622561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 166622561 = 7 ⋅23803223.

It can be written as a sum of positive squares in 2 ways, for example, as 13468900 + 151757761 = 3670^2 + 12319^2 .

It is a cyclic number.

It is not a de Polignac number, because 165226661 - 2² = 165226657 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165226681) 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 in 3 ways as a sum of consecutive naturals, for example, 9266 + ... + 20403.

It is an arithmetic number, because the mean of its divisors is an integer number (41315475).

Almost surely, 2^165226661 is an apocalyptic number.

It is an amenable number.

165226661 is a deficient number, since it is larger than the sum of its proper divisors (35239).

165226661 is an equidigital number, since it uses as much as digits as its factorization.

165226661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35238.

The product of its digits is 25920, while the sum is 35.

The square root of 165226661 is about 12854.0523182380. The cubic root of 165226661 is about 548.7316901752.

The spelling of 165226661 in words is "one hundred sixty-five million, two hundred twenty-six thousand, six hundred sixty-one".