161271666 has 12 divisors (see below), whose sum is σ = 349421982. Its totient is φ = 53757216.

The previous prime is 161271659. The next prime is 161271683. The reversal of 161271666 is 666172161.

It can be written as a sum of positive squares in only one way, i.e., 86881041 + 74390625 = 9321^2 + 8625^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 161271666.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4479751 + ... + 4479786.

Almost surely, 2^161271666 is an apocalyptic number.

161271666 is an abundant number, since it is smaller than the sum of its proper divisors (188150316).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

161271666 is a wasteful number, since it uses less digits than its factorization.

161271666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8959545 (or 8959542 counting only the distinct ones).

The product of its digits is 18144, while the sum is 36.

The square root of 161271666 is about 12699.2781684630. The cubic root of 161271666 is about 544.3179932378.

The spelling of 161271666 in words is "one hundred sixty-one million, two hundred seventy-one thousand, six hundred sixty-six".