643260166 has 16 divisors (see below), whose sum is σ = 980950320. Its totient is φ = 316293120.

The previous prime is 643260157. The next prime is 643260187. The reversal of 643260166 is 661062346.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 82150 + ... + 89638.

It is an arithmetic number, because the mean of its divisors is an integer number (61309395).

Almost surely, 2^643260166 is an apocalyptic number.

643260166 is a deficient number, since it is larger than the sum of its proper divisors (337690154).

643260166 is a wasteful number, since it uses less digits than its factorization.

643260166 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8199.

The product of its (nonzero) digits is 31104, while the sum is 34.

The square root of 643260166 is about 25362.5741201480. The cubic root of 643260166 is about 863.2346930761.

The spelling of 643260166 in words is "six hundred forty-three million, two hundred sixty thousand, one hundred sixty-six".