161680042 has 8 divisors (see below), whose sum is σ = 242868132. Its totient is φ = 80724000.

The previous prime is 161680033. The next prime is 161680111. The reversal of 161680042 is 240086161.

It can be written as a sum of positive squares in 2 ways, for example, as 119443041 + 42237001 = 10929^2 + 6499^2 .

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

It is a super-2 number, since 2×161680042² = 52280871962243528, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 56259 + ... + 59062.

Almost surely, 2^161680042 is an apocalyptic number.

161680042 is a deficient number, since it is larger than the sum of its proper divisors (81188090).

161680042 is a wasteful number, since it uses less digits than its factorization.

161680042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116024.

The product of its (nonzero) digits is 2304, while the sum is 28.

The square root of 161680042 is about 12715.3467117495. The cubic root of 161680042 is about 544.7770510242. Note that the first 3 decimals are identical.

The spelling of 161680042 in words is "one hundred sixty-one million, six hundred eighty thousand, forty-two".