166665501 has 48 divisors (see below), whose sum is σ = 266760000. Its totient is φ = 99823104.

The previous prime is 166665493. The next prime is 166665503. The reversal of 166665501 is 105566661.

It is not a de Polignac number, because 166665501 - 2³ = 166665493 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166665503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 333750 + ... + 334248.

It is an arithmetic number, because the mean of its divisors is an integer number (5557500).

Almost surely, 2^166665501 is an apocalyptic number.

It is an amenable number.

166665501 is a deficient number, since it is larger than the sum of its proper divisors (100094499).

166665501 is a wasteful number, since it uses less digits than its factorization.

166665501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 618 (or 615 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 36.

The square root of 166665501 is about 12909.8993412032. The cubic root of 166665501 is about 550.3199251639.

The spelling of 166665501 in words is "one hundred sixty-six million, six hundred sixty-five thousand, five hundred one".