643520034044 has 24 divisors (see below), whose sum is σ = 1185493063440. Its totient is φ = 304809485184.

The previous prime is 643520034043. The next prime is 643520034071. The reversal of 643520034044 is 440430025346.

It is a junction number, because it is equal to n+sod(n) for n = 643520033995 and 643520034013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643520034043) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1328462 + ... + 1746954.

It is an arithmetic number, because the mean of its divisors is an integer number (49395544310).

Almost surely, 2^643520034044 is an apocalyptic number.

It is an amenable number.

643520034044 is a deficient number, since it is larger than the sum of its proper divisors (541973029396).

643520034044 is a wasteful number, since it uses less digits than its factorization.

643520034044 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 438749 (or 438747 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 35.

The spelling of 643520034044 in words is "six hundred forty-three billion, five hundred twenty million, thirty-four thousand, forty-four".