166390861 has 8 divisors (see below), whose sum is σ = 204788864. Its totient is φ = 131649840.

The previous prime is 166390841. The next prime is 166390867. The reversal of 166390861 is 168093661.

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

It is not a de Polignac number, because 166390861 - 2²¹ = 164293709 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166390867) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 914145 + ... + 914326.

It is an arithmetic number, because the mean of its divisors is an integer number (25598608).

Almost surely, 2^166390861 is an apocalyptic number.

It is an amenable number.

166390861 is a deficient number, since it is larger than the sum of its proper divisors (38398003).

166390861 is a wasteful number, since it uses less digits than its factorization.

166390861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1828491.

The product of its (nonzero) digits is 46656, while the sum is 40.

The square root of 166390861 is about 12899.2581569639. The cubic root of 166390861 is about 550.0174771306.

The spelling of 166390861 in words is "one hundred sixty-six million, three hundred ninety thousand, eight hundred sixty-one".