161771636 has 12 divisors (see below), whose sum is σ = 304877412. Its totient is φ = 74663808.

The previous prime is 161771629. The next prime is 161771641. The reversal of 161771636 is 636177161.

It can be written as a sum of positive squares in 2 ways, for example, as 18011536 + 143760100 = 4244^2 + 11990^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 161771636.

It is a congruent number.

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, 1555445 + ... + 1555548.

It is an arithmetic number, because the mean of its divisors is an integer number (25406451).

Almost surely, 2^161771636 is an apocalyptic number.

It is an amenable number.

161771636 is a deficient number, since it is larger than the sum of its proper divisors (143105776).

161771636 is a wasteful number, since it uses less digits than its factorization.

161771636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3111010 (or 3111008 counting only the distinct ones).

The product of its digits is 31752, while the sum is 38.

The square root of 161771636 is about 12718.9479124651. The cubic root of 161771636 is about 544.8799062042.

The spelling of 161771636 in words is "one hundred sixty-one million, seven hundred seventy-one thousand, six hundred thirty-six".