66868615013 has 4 divisors (see below), whose sum is σ = 66870199200. Its totient is φ = 66867030828.

The previous prime is 66868614949. The next prime is 66868615027. The reversal of 66868615013 is 31051686866.

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 66868615013 - 2⁶ = 66868614949 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66868615043) 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, 726995 + ... + 813792.

It is an arithmetic number, because the mean of its divisors is an integer number (16717549800).

Almost surely, 2^66868615013 is an apocalyptic number.

It is an amenable number.

66868615013 is a deficient number, since it is larger than the sum of its proper divisors (1584187).

66868615013 is a wasteful number, since it uses less digits than its factorization.

66868615013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1584186.

The product of its (nonzero) digits is 1244160, while the sum is 50.

The spelling of 66868615013 in words is "sixty-six billion, eight hundred sixty-eight million, six hundred fifteen thousand, thirteen".