668313161 has 4 divisors (see below), whose sum is σ = 684613524. Its totient is φ = 652012800.

The previous prime is 668313101. The next prime is 668313209. The reversal of 668313161 is 161313866.

It is a happy number.

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 390457600 + 277855561 = 19760^2 + 16669^2 .

It is a cyclic number.

It is not a de Polignac number, because 668313161 - 2¹⁴ = 668296777 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (668313101) 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, 8150120 + ... + 8150201.

It is an arithmetic number, because the mean of its divisors is an integer number (171153381).

Almost surely, 2^668313161 is an apocalyptic number.

It is an amenable number.

668313161 is a deficient number, since it is larger than the sum of its proper divisors (16300363).

668313161 is a wasteful number, since it uses less digits than its factorization.

668313161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16300362.

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

The square root of 668313161 is about 25851.7535382032. The cubic root of 668313161 is about 874.2990461329.

The spelling of 668313161 in words is "six hundred sixty-eight million, three hundred thirteen thousand, one hundred sixty-one".