673561538729 has 4 divisors (see below), whose sum is σ = 673567061376. Its totient is φ = 673556016084.

The previous prime is 673561538659. The next prime is 673561538731. The reversal of 673561538729 is 927835165376.

673561538729 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 673561538729 - 2²⁰ = 673560490153 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (673561538129) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2574149 + ... + 2823714.

It is an arithmetic number, because the mean of its divisors is an integer number (168391765344).

Almost surely, 2^673561538729 is an apocalyptic number.

It is an amenable number.

673561538729 is a deficient number, since it is larger than the sum of its proper divisors (5522647).

673561538729 is a wasteful number, since it uses less digits than its factorization.

673561538729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5522646.

The product of its digits is 57153600, while the sum is 62.

The spelling of 673561538729 in words is "six hundred seventy-three billion, five hundred sixty-one million, five hundred thirty-eight thousand, seven hundred twenty-nine".