161188417 has 4 divisors (see below), whose sum is σ = 173587540. Its totient is φ = 148789296.

The previous prime is 161188411. The next prime is 161188429. The reversal of 161188417 is 714881161.

It is a Cunningham number, because it is equal to 12696²+1.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 714881161 = 17 ⋅42051833.

It can be written as a sum of positive squares in 2 ways, for example, as 23853456 + 137334961 = 4884^2 + 11719^2 .

It is a cyclic number.

It is not a de Polignac number, because 161188417 - 2¹⁹ = 160664129 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161188411) 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, 6199542 + ... + 6199567.

It is an arithmetic number, because the mean of its divisors is an integer number (43396885).

Almost surely, 2^161188417 is an apocalyptic number.

It is an amenable number.

161188417 is a deficient number, since it is larger than the sum of its proper divisors (12399123).

161188417 is a wasteful number, since it uses less digits than its factorization.

161188417 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12399122.

The product of its digits is 10752, while the sum is 37.

The square root of 161188417 is about 12696.0000393825. Note that the first 4 decimals coincide. The cubic root of 161188417 is about 544.2243174979.

The spelling of 161188417 in words is "one hundred sixty-one million, one hundred eighty-eight thousand, four hundred seventeen".