643066986 has 8 divisors (see below), whose sum is σ = 1286133984. Its totient is φ = 214355660.

The previous prime is 643066981. The next prime is 643066999. The reversal of 643066986 is 689660346.

It is a sphenic number, since it is the product of 3 distinct primes.

643066986 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (643066981) 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, 53588910 + ... + 53588921.

It is an arithmetic number, because the mean of its divisors is an integer number (160766748).

Almost surely, 2^643066986 is an apocalyptic number.

643066986 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

643066986 is a wasteful number, since it uses less digits than its factorization.

643066986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107177836.

The product of its (nonzero) digits is 1119744, while the sum is 48.

The square root of 643066986 is about 25358.7654667967. The cubic root of 643066986 is about 863.1482706180.

The spelling of 643066986 in words is "six hundred forty-three million, sixty-six thousand, nine hundred eighty-six".