643507450 has 48 divisors (see below), whose sum is σ = 1228983840. Its totient is φ = 250585920.

The previous prime is 643507429. The next prime is 643507457. The reversal of 643507450 is 54705346.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (643507457) 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, 367477 + ... + 369223.

It is an arithmetic number, because the mean of its divisors is an integer number (25603830).

Almost surely, 2^643507450 is an apocalyptic number.

643507450 is a deficient number, since it is larger than the sum of its proper divisors (585476390).

643507450 is a wasteful number, since it uses less digits than its factorization.

643507450 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1951 (or 1946 counting only the distinct ones).

The product of its (nonzero) digits is 50400, while the sum is 34.

The square root of 643507450 is about 25367.4486300850. The cubic root of 643507450 is about 863.3452946603.

The spelling of 643507450 in words is "six hundred forty-three million, five hundred seven thousand, four hundred fifty".