166201649 has 4 divisors (see below), whose sum is σ = 166608420. Its totient is φ = 165794880.

The previous prime is 166201631. The next prime is 166201681. The reversal of 166201649 is 946102661.

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

It can be written as a sum of positive squares in 2 ways, for example, as 157051024 + 9150625 = 12532^2 + 3025^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166201649 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (166401649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 202772 + ... + 203589.

It is an arithmetic number, because the mean of its divisors is an integer number (41652105).

Almost surely, 2^166201649 is an apocalyptic number.

It is an amenable number.

166201649 is a deficient number, since it is larger than the sum of its proper divisors (406771).

166201649 is an equidigital number, since it uses as much as digits as its factorization.

166201649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 406770.

The product of its (nonzero) digits is 15552, while the sum is 35.

The square root of 166201649 is about 12891.9218505233. The cubic root of 166201649 is about 549.8089132326.

The spelling of 166201649 in words is "one hundred sixty-six million, two hundred one thousand, six hundred forty-nine".