643423120635 has 16 divisors (see below), whose sum is σ = 1031145528096. Its totient is φ = 342602819328.

The previous prime is 643423120597. The next prime is 643423120663. The reversal of 643423120635 is 536021324346.

It is not a de Polignac number, because 643423120635 - 2¹⁰ = 643423119611 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 643423120593 and 643423120602.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 34751584 + ... + 34770093.

It is an arithmetic number, because the mean of its divisors is an integer number (64446595506).

Almost surely, 2^643423120635 is an apocalyptic number.

643423120635 is a deficient number, since it is larger than the sum of its proper divisors (387722407461).

643423120635 is a wasteful number, since it uses less digits than its factorization.

643423120635 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69522302.

The product of its (nonzero) digits is 311040, while the sum is 39.

The spelling of 643423120635 in words is "six hundred forty-three billion, four hundred twenty-three million, one hundred twenty thousand, six hundred thirty-five".