166361819 has 4 divisors (see below), whose sum is σ = 179158896. Its totient is φ = 153564744.

The previous prime is 166361809. The next prime is 166361827. The reversal of 166361819 is 918163661.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 166361819 - 2⁴ = 166361803 is a prime.

It is a super-2 number, since 2×166361819² = 55352509641977522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166361809) 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, 6398519 + ... + 6398544.

It is an arithmetic number, because the mean of its divisors is an integer number (44789724).

Almost surely, 2^166361819 is an apocalyptic number.

166361819 is a deficient number, since it is larger than the sum of its proper divisors (12797077).

166361819 is a wasteful number, since it uses less digits than its factorization.

166361819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12797076.

The product of its digits is 46656, while the sum is 41.

The square root of 166361819 is about 12898.1323841865. The cubic root of 166361819 is about 549.9854750985.

The spelling of 166361819 in words is "one hundred sixty-six million, three hundred sixty-one thousand, eight hundred nineteen".