168669561636 has 27 divisors (see below), whose sum is σ = 426365398641. Its totient is φ = 56222365824.

The previous prime is 168669561629. The next prime is 168669561647. The reversal of 168669561636 is 636165966861.

It is a happy number.

The square root of 168669561636 is 410694.

It is a perfect power (a square), and thus also a powerful number.

168669561636 is a `hidden beast` number, since 1 + 6 + 8 + 6 + 6 + 9 + 5 + 616 + 3 + 6 = 666.

It can be written as a sum of positive squares in only one way, i.e., 10711008036 + 157958553600 = 103494^2 + 397440^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 2429940 + ... + 2498388.

Almost surely, 2^168669561636 is an apocalyptic number.

168669561636 is the 410694-th square number.

It is an amenable number.

168669561636 is an abundant number, since it is smaller than the sum of its proper divisors (257695837005).

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

168669561636 is an frugal number, since it uses more digits than its factorization.

168669561636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136908 (or 68454 counting only the distinct ones).

The product of its digits is 50388480, while the sum is 63.

The spelling of 168669561636 in words is "one hundred sixty-eight billion, six hundred sixty-nine million, five hundred sixty-one thousand, six hundred thirty-six".