161660817 has 12 divisors (see below), whose sum is σ = 234443664. Its totient is φ = 107343000.

The previous prime is 161660791. The next prime is 161660833. The reversal of 161660817 is 718066161.

It is not a de Polignac number, because 161660817 - 2⁷ = 161660689 is a prime.

It is a super-2 number, since 2×161660817² = 52268439506214978, which contains 22 as substring.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (161660887) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 33523 + ... + 38040.

It is an arithmetic number, because the mean of its divisors is an integer number (19536972).

Almost surely, 2^161660817 is an apocalyptic number.

It is an amenable number.

161660817 is a deficient number, since it is larger than the sum of its proper divisors (72782847).

161660817 is a wasteful number, since it uses less digits than its factorization.

161660817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71820 (or 71817 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 36.

The square root of 161660817 is about 12714.5907130352. The cubic root of 161660817 is about 544.7554574417.

The spelling of 161660817 in words is "one hundred sixty-one million, six hundred sixty thousand, eight hundred seventeen".