166981093 has 4 divisors (see below), whose sum is σ = 167071840. Its totient is φ = 166890348.

The previous prime is 166981079. The next prime is 166981103. The reversal of 166981093 is 390189661.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 166981093 - 2²⁵ = 133426661 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166901093) 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 3 ways as a sum of consecutive naturals, for example, 42555 + ... + 46312.

It is an arithmetic number, because the mean of its divisors is an integer number (41767960).

Almost surely, 2^166981093 is an apocalyptic number.

It is an amenable number.

166981093 is a deficient number, since it is larger than the sum of its proper divisors (90747).

166981093 is an equidigital number, since it uses as much as digits as its factorization.

166981093 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90746.

The product of its (nonzero) digits is 69984, while the sum is 43.

The square root of 166981093 is about 12922.1164288208. The cubic root of 166981093 is about 550.6670617085.

The spelling of 166981093 in words is "one hundred sixty-six million, nine hundred eighty-one thousand, ninety-three".