161636 has 12 divisors (see below), whose sum is σ = 299628. Its totient is φ = 76032.

The previous prime is 161627. The next prime is 161639. The reversal of 161636 is 636161.

It can be written as a sum of positive squares in 2 ways, for example, as 96100 + 65536 = 310^2 + 256^2 .

It is a super-2 number, since 2×161636² = 52252392992, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (161639) 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, 1121 + ... + 1256.

It is an arithmetic number, because the mean of its divisors is an integer number (24969).

2¹⁶¹⁶³⁶ is an apocalyptic number.

It is an amenable number.

161636 is a deficient number, since it is larger than the sum of its proper divisors (137992).

161636 is a wasteful number, since it uses less digits than its factorization.

161636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2398 (or 2396 counting only the distinct ones).

The product of its digits is 648, while the sum is 23.

The square root of 161636 is about 402.0397990249. The cubic root of 161636 is about 54.4727580375.

Adding to 161636 its reverse (636161), we get a palindrome (797797).

It can be divided in two parts, 161 and 636, that added together give a palindrome (797).

The spelling of 161636 in words is "one hundred sixty-one thousand, six hundred thirty-six".