161365613 has 4 divisors (see below), whose sum is σ = 169858560. Its totient is φ = 152872668.

The previous prime is 161365609. The next prime is 161365619. The reversal of 161365613 is 316563161.

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 161365613 - 2² = 161365609 is a prime.

It is a super-2 number, since 2×161365613² = 52077722117731538, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 161365613.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161365619) 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, 4246445 + ... + 4246482.

It is an arithmetic number, because the mean of its divisors is an integer number (42464640).

Almost surely, 2^161365613 is an apocalyptic number.

It is an amenable number.

161365613 is a deficient number, since it is larger than the sum of its proper divisors (8492947).

161365613 is an equidigital number, since it uses as much as digits as its factorization.

161365613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8492946.

The product of its digits is 9720, while the sum is 32.

The square root of 161365613 is about 12702.9765409529. The cubic root of 161365613 is about 544.4236681676.

The spelling of 161365613 in words is "one hundred sixty-one million, three hundred sixty-five thousand, six hundred thirteen".