165005611 has 4 divisors (see below), whose sum is σ = 172179792. Its totient is φ = 157831432.

The previous prime is 165005551. The next prime is 165005627. The reversal of 165005611 is 116500561.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 116500561 = 9931 ⋅11731.

It is a cyclic number.

It is not a de Polignac number, because 165005611 - 2¹³ = 164997419 is a prime.

It is a super-2 number, since 2×165005611² = 54453703322966642, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165000611) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3587056 + ... + 3587101.

It is an arithmetic number, because the mean of its divisors is an integer number (43044948).

Almost surely, 2^165005611 is an apocalyptic number.

165005611 is a deficient number, since it is larger than the sum of its proper divisors (7174181).

165005611 is an equidigital number, since it uses as much as digits as its factorization.

165005611 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7174180.

The product of its (nonzero) digits is 900, while the sum is 25.

The square root of 165005611 is about 12845.4509846871. The cubic root of 165005611 is about 548.4868723949.

The spelling of 165005611 in words is "one hundred sixty-five million, five thousand, six hundred eleven".