643322523706 has 4 divisors (see below), whose sum is σ = 964983785562. Its totient is φ = 321661261852.

The previous prime is 643322523653. The next prime is 643322523713. The reversal of 643322523706 is 607325223346.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 641506485481 + 1816038225 = 800941^2 + 42615^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160830630925 + ... + 160830630928.

Almost surely, 2^643322523706 is an apocalyptic number.

643322523706 is a deficient number, since it is larger than the sum of its proper divisors (321661261856).

643322523706 is a wasteful number, since it uses less digits than its factorization.

643322523706 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 321661261855.

The product of its (nonzero) digits is 1088640, while the sum is 43.

The spelling of 643322523706 in words is "six hundred forty-three billion, three hundred twenty-two million, five hundred twenty-three thousand, seven hundred six".