643523475 has 24 divisors (see below), whose sum is σ = 1215953920. Its totient is φ = 294181920.

The previous prime is 643523459. The next prime is 643523477. The reversal of 643523475 is 574325346.

It is not a de Polignac number, because 643523475 - 2⁴ = 643523459 is a prime.

It is not an unprimeable number, because it can be changed into a prime (643523477) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 612355 + ... + 613404.

Almost surely, 2^643523475 is an apocalyptic number.

643523475 is a deficient number, since it is larger than the sum of its proper divisors (572430445).

643523475 is a wasteful number, since it uses less digits than its factorization.

643523475 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1225779 (or 1225774 counting only the distinct ones).

The product of its digits is 302400, while the sum is 39.

The square root of 643523475 is about 25367.7644856617. The cubic root of 643523475 is about 863.3524611111.

The spelling of 643523475 in words is "six hundred forty-three million, five hundred twenty-three thousand, four hundred seventy-five".