161615817 has 20 divisors (see below), whose sum is σ = 263375376. Its totient is φ = 97948440.

The previous prime is 161615807. The next prime is 161615819. The reversal of 161615817 is 718516161.

161615817 is a `hidden beast` number, since 16 + 1 + 61 + 581 + 7 = 666.

It is not a de Polignac number, because 161615817 - 2¹¹ = 161613769 is a prime.

It is a super-2 number, since 2×161615817² = 52239344609154978, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (161615819) 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 19 ways as a sum of consecutive naturals, for example, 89803 + ... + 91584.

Almost surely, 2^161615817 is an apocalyptic number.

It is an amenable number.

161615817 is a deficient number, since it is larger than the sum of its proper divisors (101759559).

161615817 is a wasteful number, since it uses less digits than its factorization.

161615817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 181410 (or 181401 counting only the distinct ones).

The product of its digits is 10080, while the sum is 36.

The square root of 161615817 is about 12712.8209693994. The cubic root of 161615817 is about 544.7049066013.

The spelling of 161615817 in words is "one hundred sixty-one million, six hundred fifteen thousand, eight hundred seventeen".