161682309 has 6 divisors (see below), whose sum is σ = 233541126. Its totient is φ = 107788200.

The previous prime is 161682307. The next prime is 161682317. The reversal of 161682309 is 903286161.

161682309 is a `hidden beast` number, since 1 + 616 + 8 + 2 + 30 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 160731684 + 950625 = 12678^2 + 975^2 .

It is not a de Polignac number, because 161682309 - 2¹ = 161682307 is a prime.

It is a super-2 number, since 2×161682309² = 52282338087142962, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161682307) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 8982342 + ... + 8982359.

It is an arithmetic number, because the mean of its divisors is an integer number (38923521).

Almost surely, 2^161682309 is an apocalyptic number.

It is an amenable number.

161682309 is a deficient number, since it is larger than the sum of its proper divisors (71858817).

161682309 is a wasteful number, since it uses less digits than its factorization.

161682309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17964707 (or 17964704 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 161682309 is about 12715.4358556834. The cubic root of 161682309 is about 544.7795972131.

The spelling of 161682309 in words is "one hundred sixty-one million, six hundred eighty-two thousand, three hundred nine".