66613315641 has 4 divisors (see below), whose sum is σ = 88817754192. Its totient is φ = 44408877092.

The previous prime is 66613315603. The next prime is 66613315649. The reversal of 66613315641 is 14651331666.

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 66613315641 - 2⁶ = 66613315577 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66613315593 and 66613315602.

It is not an unprimeable number, because it can be changed into a prime (66613315649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11102219271 + ... + 11102219276.

It is an arithmetic number, because the mean of its divisors is an integer number (22204438548).

Almost surely, 2^66613315641 is an apocalyptic number.

It is an amenable number.

66613315641 is a deficient number, since it is larger than the sum of its proper divisors (22204438551).

66613315641 is a wasteful number, since it uses less digits than its factorization.

66613315641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22204438550.

The product of its digits is 233280, while the sum is 42.

The spelling of 66613315641 in words is "sixty-six billion, six hundred thirteen million, three hundred fifteen thousand, six hundred forty-one".