161611669 has 4 divisors (see below), whose sum is σ = 161662720. Its totient is φ = 161560620.

The previous prime is 161611661. The next prime is 161611699. The reversal of 161611669 is 966116161.

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 a cyclic number.

It is not a de Polignac number, because 161611669 - 2³ = 161611661 is a prime.

It is a super-2 number, since 2×161611669² = 52236663113931122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161611661) 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, 20439 + ... + 27220.

It is an arithmetic number, because the mean of its divisors is an integer number (40415680).

Almost surely, 2^161611669 is an apocalyptic number.

It is an amenable number.

161611669 is a deficient number, since it is larger than the sum of its proper divisors (51051).

161611669 is an equidigital number, since it uses as much as digits as its factorization.

161611669 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51050.

The product of its digits is 11664, while the sum is 37.

The square root of 161611669 is about 12712.6578259623. The cubic root of 161611669 is about 544.7002464648.

The spelling of 161611669 in words is "one hundred sixty-one million, six hundred eleven thousand, six hundred sixty-nine".