643440502 has 16 divisors (see below), whose sum is σ = 1014485472. Its totient is φ = 305483200.

The previous prime is 643440493. The next prime is 643440509. The reversal of 643440502 is 205044346.

It is a super-2 number, since 2×643440502² = 828031359228024008, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643440509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44749 + ... + 57352.

It is an arithmetic number, because the mean of its divisors is an integer number (63405342).

Almost surely, 2^643440502 is an apocalyptic number.

643440502 is a deficient number, since it is larger than the sum of its proper divisors (371044970).

643440502 is a wasteful number, since it uses less digits than its factorization.

643440502 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102263.

The product of its (nonzero) digits is 11520, while the sum is 28.

The square root of 643440502 is about 25366.1290306582. The cubic root of 643440502 is about 863.3153539319.

Adding to 643440502 its reverse (205044346), we get a palindrome (848484848).

The spelling of 643440502 in words is "six hundred forty-three million, four hundred forty thousand, five hundred two".