165566236666 has 16 divisors (see below), whose sum is σ = 251369026920. Its totient is φ = 81778259200.

The previous prime is 165566236663. The next prime is 165566236699. The reversal of 165566236666 is 666632665561.

It can be written as a sum of positive squares in 4 ways, for example, as 129553204225 + 36013032441 = 359935^2 + 189771^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 165566236666.

It is not an unprimeable number, because it can be changed into a prime (165566236663) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 228685 + ... + 619216.

Almost surely, 2^165566236666 is an apocalyptic number.

165566236666 is a deficient number, since it is larger than the sum of its proper divisors (85802790254).

165566236666 is a wasteful number, since it uses less digits than its factorization.

165566236666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 849089.

The product of its digits is 41990400, while the sum is 58.

The spelling of 165566236666 in words is "one hundred sixty-five billion, five hundred sixty-six million, two hundred thirty-six thousand, six hundred sixty-six".