643517234 has 4 divisors (see below), whose sum is σ = 965275854. Its totient is φ = 321758616.

The previous prime is 643517219. The next prime is 643517267. The reversal of 643517234 is 432715346.

643517234 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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., 424566025 + 218951209 = 20605^2 + 14797^2 .

It is a super-2 number, since 2×643517234² = 828228860910021512, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 643517194 and 643517203.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160879307 + ... + 160879310.

Almost surely, 2^643517234 is an apocalyptic number.

643517234 is a deficient number, since it is larger than the sum of its proper divisors (321758620).

643517234 is a wasteful number, since it uses less digits than its factorization.

643517234 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 321758619.

The product of its digits is 60480, while the sum is 35.

The square root of 643517234 is about 25367.6414749184. The cubic root of 643517234 is about 863.3496701225.

The spelling of 643517234 in words is "six hundred forty-three million, five hundred seventeen thousand, two hundred thirty-four".