161217161 has 8 divisors (see below), whose sum is σ = 184553664. Its totient is φ = 137957040.

The previous prime is 161217139. The next prime is 161217163. The reversal of 161217161 is 161712161.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 161217161 - 2²⁶ = 94108297 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 161217161.

It is not an unprimeable number, because it can be changed into a prime (161217163) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14495 + ... + 23076.

It is an arithmetic number, because the mean of its divisors is an integer number (23069208).

Almost surely, 2^161217161 is an apocalyptic number.

It is an amenable number.

161217161 is a deficient number, since it is larger than the sum of its proper divisors (23336503).

161217161 is an equidigital number, since it uses as much as digits as its factorization.

161217161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38191.

The product of its digits is 504, while the sum is 26.

The square root of 161217161 is about 12697.1319989988. The cubic root of 161217161 is about 544.2566652607.

The spelling of 161217161 in words is "one hundred sixty-one million, two hundred seventeen thousand, one hundred sixty-one".