161761666 has 8 divisors (see below), whose sum is σ = 264700944. Its totient is φ = 73528020.

The previous prime is 161761661. The next prime is 161761693. The reversal of 161761666 is 666167161.

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

It is not an unprimeable number, because it can be changed into a prime (161761661) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3676380 + ... + 3676423.

It is an arithmetic number, because the mean of its divisors is an integer number (33087618).

Almost surely, 2^161761666 is an apocalyptic number.

161761666 is a deficient number, since it is larger than the sum of its proper divisors (102939278).

161761666 is a wasteful number, since it uses less digits than its factorization.

161761666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7352816.

The product of its digits is 54432, while the sum is 40.

The square root of 161761666 is about 12718.5559714930. Note that the first 3 decimals coincide. The cubic root of 161761666 is about 544.8687123089.

The spelling of 161761666 in words is "one hundred sixty-one million, seven hundred sixty-one thousand, six hundred sixty-six".