166605151555565 has 16 divisors (see below), whose sum is σ = 210880745224320. Its totient is φ = 126009887855040.

The previous prime is 166605151555559. The next prime is 166605151555589. The reversal of 166605151555565 is 565555151506661.

It is not a de Polignac number, because 166605151555565 - 2¹⁸ = 166605151293421 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 166605151555498 and 166605151555507.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1800506546 + ... + 1800599075.

It is an arithmetic number, because the mean of its divisors is an integer number (13180046576520).

Almost surely, 2^{166605151555565} is an apocalyptic number.

It is an amenable number.

166605151555565 is a deficient number, since it is larger than the sum of its proper divisors (44275593668755).

166605151555565 is a wasteful number, since it uses less digits than its factorization.

166605151555565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3601106132.

The product of its (nonzero) digits is 101250000, while the sum is 62.

The spelling of 166605151555565 in words is "one hundred sixty-six trillion, six hundred five billion, one hundred fifty-one million, five hundred fifty-five thousand, five hundred sixty-five".