161723399 has 4 divisors (see below), whose sum is σ = 161826264. Its totient is φ = 161620536.

The previous prime is 161723357. The next prime is 161723417. The reversal of 161723399 is 993327161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 993327161 = 6473 ⋅153457.

It is a cyclic number.

It is not a de Polignac number, because 161723399 - 2²⁴ = 144946183 is a prime.

It is a super-2 number, since 2×161723399² = 52308915568226402, 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 (161723339) 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, 49037 + ... + 52230.

It is an arithmetic number, because the mean of its divisors is an integer number (40456566).

Almost surely, 2^161723399 is an apocalyptic number.

161723399 is a deficient number, since it is larger than the sum of its proper divisors (102865).

161723399 is a wasteful number, since it uses less digits than its factorization.

161723399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102864.

The product of its digits is 61236, while the sum is 41.

The square root of 161723399 is about 12717.0515057540. The cubic root of 161723399 is about 544.8257434649.

The spelling of 161723399 in words is "one hundred sixty-one million, seven hundred twenty-three thousand, three hundred ninety-nine".