161797 has 4 divisors (see below), whose sum is σ = 163116. Its totient is φ = 160480.

The previous prime is 161783. The next prime is 161807. The reversal of 161797 is 797161.

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 125316 + 36481 = 354^2 + 191^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161797 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161717) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 454 + ... + 727.

It is an arithmetic number, because the mean of its divisors is an integer number (40779).

2¹⁶¹⁷⁹⁷ is an apocalyptic number.

It is an amenable number.

161797 is a deficient number, since it is larger than the sum of its proper divisors (1319).

161797 is a wasteful number, since it uses less digits than its factorization.

161797 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1318.

The product of its digits is 2646, while the sum is 31.

The square root of 161797 is about 402.2399781225. The cubic root of 161797 is about 54.4908381760.

The spelling of 161797 in words is "one hundred sixty-one thousand, seven hundred ninety-seven".