643666614 has 16 divisors (see below), whose sum is σ = 1363058928. Its totient is φ = 201934592.

The previous prime is 643666579. The next prime is 643666619. The reversal of 643666614 is 416666346.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643666619) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3155127 + ... + 3155330.

It is an arithmetic number, because the mean of its divisors is an integer number (85191183).

Almost surely, 2^643666614 is an apocalyptic number.

643666614 is an abundant number, since it is smaller than the sum of its proper divisors (719392314).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

643666614 is a wasteful number, since it uses less digits than its factorization.

643666614 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6310479.

The product of its digits is 373248, while the sum is 42.

The square root of 643666614 is about 25370.5856061700. The cubic root of 643666614 is about 863.4164682278.

The spelling of 643666614 in words is "six hundred forty-three million, six hundred sixty-six thousand, six hundred fourteen".