161423377 has 4 divisors (see below), whose sum is σ = 161455140. Its totient is φ = 161391616.

The previous prime is 161423329. The next prime is 161423387. The reversal of 161423377 is 773324161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 773324161 = 37 ⋅20900653.

It can be written as a sum of positive squares in 2 ways, for example, as 39740416 + 121682961 = 6304^2 + 11031^2 .

It is a 3-Lehmer number, since φ(161423377) divides (161423377-1)³.

It is a cyclic number.

It is not a de Polignac number, because 161423377 - 2²⁷ = 27205649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161423387) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6352 + ... + 19057.

It is an arithmetic number, because the mean of its divisors is an integer number (40363785).

It is a Poulet number, since it divides 2^161423376-1.

Almost surely, 2^161423377 is an apocalyptic number.

161423377 is the 6353-rd decagonal number.

It is an amenable number.

161423377 is a deficient number, since it is larger than the sum of its proper divisors (31763).

161423377 is an equidigital number, since it uses as much as digits as its factorization.

161423377 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31762.

The product of its digits is 21168, while the sum is 34.

The square root of 161423377 is about 12705.2499778635. The cubic root of 161423377 is about 544.4886228100.

The spelling of 161423377 in words is "one hundred sixty-one million, four hundred twenty-three thousand, three hundred seventy-seven".