161369 has 4 divisors (see below), whose sum is σ = 173796. Its totient is φ = 148944.

The previous prime is 161363. The next prime is 161377. The reversal of 161369 is 963161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 963161 = 227 ⋅4243.

It can be written as a sum of positive squares in 2 ways, for example, as 35344 + 126025 = 188^2 + 355^2 .

It is a cyclic number.

It is not a de Polignac number, because 161369 - 2¹² = 157273 is a prime.

It is a super-2 number, since 2×161369² = 52079908322, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161363) 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, 6194 + ... + 6219.

It is an arithmetic number, because the mean of its divisors is an integer number (43449).

2¹⁶¹³⁶⁹ is an apocalyptic number.

It is an amenable number.

161369 is a deficient number, since it is larger than the sum of its proper divisors (12427).

161369 is a wasteful number, since it uses less digits than its factorization.

161369 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12426.

The product of its digits is 972, while the sum is 26.

The square root of 161369 is about 401.7076051060. The cubic root of 161369 is about 54.4427477220.

It can be divided in two parts, 16 and 1369, that multiplied together give a square (21904 = 148²).

The spelling of 161369 in words is "one hundred sixty-one thousand, three hundred sixty-nine".