161634 has 32 divisors (see below), whose sum is σ = 368640. Its totient is φ = 46800.

The previous prime is 161627. The next prime is 161639. The reversal of 161634 is 436161.

It is a super-2 number, since 2×161634² = 52251099912, which contains 22 as substring.

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

It is a self number, because there is not a number n which added to its sum of digits gives 161634.

It is not an unprimeable number, because it can be changed into a prime (161639) by changing a digit.

161634 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2007 + ... + 2085.

It is an arithmetic number, because the mean of its divisors is an integer number (11520).

2¹⁶¹⁶³⁴ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161634, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (184320).

161634 is an abundant number, since it is smaller than the sum of its proper divisors (207006).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

161634 is a wasteful number, since it uses less digits than its factorization.

161634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126.

The product of its digits is 432, while the sum is 21.

The square root of 161634 is about 402.0373117013. The cubic root of 161634 is about 54.4725333640.

Adding to 161634 its reverse (436161), we get a palindrome (597795).

The spelling of 161634 in words is "one hundred sixty-one thousand, six hundred thirty-four".