166640365 has 8 divisors (see below), whose sum is σ = 201074328. Its totient is φ = 132575040.

The previous prime is 166640363. The next prime is 166640377. The reversal of 166640365 is 563046661.

It can be written as a sum of positive squares in 4 ways, for example, as 3541924 + 163098441 = 1882^2 + 12771^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 166640365 - 2¹ = 166640363 is a prime.

It is a super-2 number, since 2×166640365² = 55538022494666450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166640363) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 91162 + ... + 92971.

It is an arithmetic number, because the mean of its divisors is an integer number (25134291).

Almost surely, 2^166640365 is an apocalyptic number.

It is an amenable number.

166640365 is a deficient number, since it is larger than the sum of its proper divisors (34433963).

166640365 is a wasteful number, since it uses less digits than its factorization.

166640365 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 184319.

The product of its (nonzero) digits is 77760, while the sum is 37.

The square root of 166640365 is about 12908.9257879965. The cubic root of 166640365 is about 550.2922578962.

The spelling of 166640365 in words is "one hundred sixty-six million, six hundred forty thousand, three hundred sixty-five".