161617 has 4 divisors (see below), whose sum is σ = 167220. Its totient is φ = 156016.

The previous prime is 161611. The next prime is 161627. The reversal of 161617 is 716161.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 38416 + 123201 = 196^2 + 351^2 .

It is a cyclic number.

It is not a de Polignac number, because 161617 - 2¹¹ = 159569 is a prime.

It is a super-2 number, since 2×161617² = 52240109378, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161611) 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, 2758 + ... + 2815.

It is an arithmetic number, because the mean of its divisors is an integer number (41805).

2¹⁶¹⁶¹⁷ is an apocalyptic number.

It is an amenable number.

161617 is a deficient number, since it is larger than the sum of its proper divisors (5603).

161617 is an equidigital number, since it uses as much as digits as its factorization.

161617 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5602.

The product of its digits is 252, while the sum is 22.

The square root of 161617 is about 402.0161688291. The cubic root of 161617 is about 54.4706235647.

Adding to 161617 its reverse (716161), we get a palindrome (877778).

It can be divided in two parts, 1616 and 17, that multiplied together give a palindrome (27472).

The spelling of 161617 in words is "one hundred sixty-one thousand, six hundred seventeen".