166553321255523 has 6 divisors (see below), whose sum is σ = 240577019591324. Its totient is φ = 111035547503676.

The previous prime is 166553321255509. The next prime is 166553321255593. The reversal of 166553321255523 is 325552123355661.

166553321255523 is a `hidden beast` number, since 1 + 6 + 6 + 5 + 5 + 332 + 1 + 255 + 52 + 3 = 666.

It is not a de Polignac number, because 166553321255523 - 2⁶ = 166553321255459 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 166553321255523.

It is not an unprimeable number, because it can be changed into a prime (166553321255593) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9252962291965 + ... + 9252962291982.

Almost surely, 2^{166553321255523} is an apocalyptic number.

166553321255523 is a deficient number, since it is larger than the sum of its proper divisors (74023698335801).

166553321255523 is a wasteful number, since it uses less digits than its factorization.

166553321255523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18505924583953 (or 18505924583950 counting only the distinct ones).

The product of its digits is 24300000, while the sum is 54.

The spelling of 166553321255523 in words is "one hundred sixty-six trillion, five hundred fifty-three billion, three hundred twenty-one million, two hundred fifty-five thousand, five hundred twenty-three".