166815 has 24 divisors (see below), whose sum is σ = 316368. Its totient is φ = 80640.

The previous prime is 166807. The next prime is 166823. The reversal of 166815 is 518661.

It is an interprime number because it is at equal distance from previous prime (166807) and next prime (166823).

It is not a de Polignac number, because 166815 - 2³ = 166807 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 327 + ... + 663.

It is an arithmetic number, because the mean of its divisors is an integer number (13182).

2¹⁶⁶⁸¹⁵ is an apocalyptic number.

166815 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

166815 is a deficient number, since it is larger than the sum of its proper divisors (149553).

166815 is a wasteful number, since it uses less digits than its factorization.

166815 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 359 (or 356 counting only the distinct ones).

The product of its digits is 1440, while the sum is 27.

The square root of 166815 is about 408.4299205494. The cubic root of 166815 is about 55.0484421697.

The spelling of 166815 in words is "one hundred sixty-six thousand, eight hundred fifteen".