166815049 has 4 divisors (see below), whose sum is σ = 166983364. Its totient is φ = 166646736.

The previous prime is 166815043. The next prime is 166815073. The reversal of 166815049 is 940518661.

166815049 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 940518661 = 43 ⋅21872527.

It can be written as a sum of positive squares in 2 ways, for example, as 159845449 + 6969600 = 12643^2 + 2640^2 .

It is a cyclic number.

It is not a de Polignac number, because 166815049 - 2¹⁵ = 166782281 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166815043) 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, 82662 + ... + 84655.

It is an arithmetic number, because the mean of its divisors is an integer number (41745841).

Almost surely, 2^166815049 is an apocalyptic number.

It is an amenable number.

166815049 is a deficient number, since it is larger than the sum of its proper divisors (168315).

166815049 is an equidigital number, since it uses as much as digits as its factorization.

166815049 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168314.

The product of its (nonzero) digits is 51840, while the sum is 40.

The square root of 166815049 is about 12915.6900318953. The cubic root of 166815049 is about 550.4844755966.

The spelling of 166815049 in words is "one hundred sixty-six million, eight hundred fifteen thousand, forty-nine".