643476073 has 2 divisors, whose sum is σ = 643476074. Its totient is φ = 643476072.

The previous prime is 643476049. The next prime is 643476143. The reversal of 643476073 is 370674346.

643476073 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 639685264 + 3790809 = 25292^2 + 1947^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-643476073 is a prime.

It is a super-2 number, since 2×643476073² = 828122913047002658, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (643476023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321738036 + 321738037.

It is an arithmetic number, because the mean of its divisors is an integer number (321738037).

Almost surely, 2^643476073 is an apocalyptic number.

It is an amenable number.

643476073 is a deficient number, since it is larger than the sum of its proper divisors (1).

643476073 is an equidigital number, since it uses as much as digits as its factorization.

643476073 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 254016, while the sum is 40.

The square root of 643476073 is about 25366.8301724910. The cubic root of 643476073 is about 863.3312623826.

The spelling of 643476073 in words is "six hundred forty-three million, four hundred seventy-six thousand, seventy-three".