643544234 has 8 divisors (see below), whose sum is σ = 970217028. Its totient is φ = 320138560.

The previous prime is 643544227. The next prime is 643544263. The reversal of 643544234 is 432445346.

It can be written as a sum of positive squares in 2 ways, for example, as 596580625 + 46963609 = 24425^2 + 6853^2 .

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

It is a super-2 number, since 2×643544234² = 828298362229293512, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 643544194 and 643544203.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 816287 + ... + 817074.

Almost surely, 2^643544234 is an apocalyptic number.

643544234 is a deficient number, since it is larger than the sum of its proper divisors (326672794).

643544234 is a wasteful number, since it uses less digits than its factorization.

643544234 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1633560.

The product of its digits is 138240, while the sum is 35.

The square root of 643544234 is about 25368.1736433666. The cubic root of 643544234 is about 863.3617444508.

The spelling of 643544234 in words is "six hundred forty-three million, five hundred forty-four thousand, two hundred thirty-four".