166440863 has 4 divisors (see below), whose sum is σ = 176231520. Its totient is φ = 156650208.

The previous prime is 166440851. The next prime is 166440887. The reversal of 166440863 is 368044661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 368044661 = 37 ⋅9947153.

It is a cyclic number.

It is not a de Polignac number, because 166440863 - 2⁴ = 166440847 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166442863) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4895303 + ... + 4895336.

It is an arithmetic number, because the mean of its divisors is an integer number (44057880).

Almost surely, 2^166440863 is an apocalyptic number.

166440863 is a deficient number, since it is larger than the sum of its proper divisors (9790657).

166440863 is an equidigital number, since it uses as much as digits as its factorization.

166440863 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9790656.

The product of its (nonzero) digits is 82944, while the sum is 38.

The square root of 166440863 is about 12901.1961848505. The cubic root of 166440863 is about 550.0725667337.

The spelling of 166440863 in words is "one hundred sixty-six million, four hundred forty thousand, eight hundred sixty-three".