643261746 has 16 divisors (see below), whose sum is σ = 1342459584. Its totient is φ = 205097904.

The previous prime is 643261727. The next prime is 643261747. The reversal of 643261746 is 647162346.

It is a happy number.

643261746 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (643261747) 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, 2330521 + ... + 2330796.

It is an arithmetic number, because the mean of its divisors is an integer number (83903724).

Almost surely, 2^643261746 is an apocalyptic number.

643261746 is an abundant number, since it is smaller than the sum of its proper divisors (699197838).

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

643261746 is a wasteful number, since it uses less digits than its factorization.

643261746 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4661345.

The product of its digits is 145152, while the sum is 39.

The square root of 643261746 is about 25362.6052683868. The cubic root of 643261746 is about 863.2353998454.

The spelling of 643261746 in words is "six hundred forty-three million, two hundred sixty-one thousand, seven hundred forty-six".