67661640073 has 4 divisors (see below), whose sum is σ = 67959709200. Its totient is φ = 67363570948.

The previous prime is 67661640047. The next prime is 67661640091. The reversal of 67661640073 is 37004616676.

67661640073 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 67661640073 - 2²⁵ = 67628085641 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (67661650073) 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, 149034223 + ... + 149034676.

It is an arithmetic number, because the mean of its divisors is an integer number (16989927300).

Almost surely, 2^67661640073 is an apocalyptic number.

It is an amenable number.

67661640073 is a deficient number, since it is larger than the sum of its proper divisors (298069127).

67661640073 is a wasteful number, since it uses less digits than its factorization.

67661640073 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 298069126.

The product of its (nonzero) digits is 762048, while the sum is 46.

The spelling of 67661640073 in words is "sixty-seven billion, six hundred sixty-one million, six hundred forty thousand, seventy-three".