166021564202985 has 32 divisors (see below), whose sum is σ = 279618231260160. Its totient is φ = 83883690237888.

The previous prime is 166021564202983. The next prime is 166021564203017. The reversal of 166021564202985 is 589202465120661.

It is not a de Polignac number, because 166021564202985 - 2¹ = 166021564202983 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (57).

It is not an unprimeable number, because it can be changed into a prime (166021564202983) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 24257262 + ... + 30339048.

It is an arithmetic number, because the mean of its divisors is an integer number (8738069726880).

Almost surely, 2^{166021564202985} is an apocalyptic number.

166021564202985 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

166021564202985 is a deficient number, since it is larger than the sum of its proper divisors (113596667057175).

166021564202985 is a wasteful number, since it uses less digits than its factorization.

166021564202985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6177597.

The product of its (nonzero) digits is 12441600, while the sum is 57.

The spelling of 166021564202985 in words is "one hundred sixty-six trillion, twenty-one billion, five hundred sixty-four million, two hundred two thousand, nine hundred eighty-five".