165926881 has 4 divisors (see below), whose sum is σ = 165957012. Its totient is φ = 165896752.

The previous prime is 165926879. The next prime is 165926903. The reversal of 165926881 is 188629561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 188629561 = 41 ⋅4600721.

It can be written as a sum of positive squares in 2 ways, for example, as 135024400 + 30902481 = 11620^2 + 5559^2 .

It is a cyclic number.

It is not a de Polignac number, because 165926881 - 2¹ = 165926879 is a prime.

It is a super-2 number, since 2×165926881² = 55063459676776322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165926581) 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, 4186 + ... + 18691.

It is an arithmetic number, because the mean of its divisors is an integer number (41489253).

Almost surely, 2^165926881 is an apocalyptic number.

It is an amenable number.

165926881 is a deficient number, since it is larger than the sum of its proper divisors (30131).

165926881 is an equidigital number, since it uses as much as digits as its factorization.

165926881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30130.

The product of its digits is 207360, while the sum is 46.

The square root of 165926881 is about 12881.2608466718. The cubic root of 165926881 is about 549.5057609604.

The spelling of 165926881 in words is "one hundred sixty-five million, nine hundred twenty-six thousand, eight hundred eighty-one".