161647 has 4 divisors (see below), whose sum is σ = 163240. Its totient is φ = 160056.

The previous prime is 161641. The next prime is 161659. The reversal of 161647 is 746161.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 746161 = 13 ⋅57397.

It is a cyclic number.

It is not a de Polignac number, because 161647 - 2³ = 161639 is a prime.

It is a super-2 number, since 2×161647² = 52259505218, 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 (161641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 633 + ... + 850.

It is an arithmetic number, because the mean of its divisors is an integer number (40810).

2¹⁶¹⁶⁴⁷ is an apocalyptic number.

161647 is a deficient number, since it is larger than the sum of its proper divisors (1593).

161647 is a wasteful number, since it uses less digits than its factorization.

161647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1592.

The product of its digits is 1008, while the sum is 25.

The square root of 161647 is about 402.0534790298. The cubic root of 161647 is about 54.4739937085.

It can be divided in two parts, 161 and 647, that added together give a palindrome (808).

The spelling of 161647 in words is "one hundred sixty-one thousand, six hundred forty-seven".