66151808813 has 4 divisors (see below), whose sum is σ = 66794059488. Its totient is φ = 65509558140.

The previous prime is 66151808809. The next prime is 66151808819. The reversal of 66151808813 is 31880815166.

It is a happy number.

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 66151808813 - 2² = 66151808809 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 (66151808819) 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, 321125183 + ... + 321125388.

It is an arithmetic number, because the mean of its divisors is an integer number (16698514872).

Almost surely, 2^66151808813 is an apocalyptic number.

It is an amenable number.

66151808813 is a deficient number, since it is larger than the sum of its proper divisors (642250675).

66151808813 is a wasteful number, since it uses less digits than its factorization.

66151808813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 642250674.

The product of its (nonzero) digits is 276480, while the sum is 47.

The spelling of 66151808813 in words is "sixty-six billion, one hundred fifty-one million, eight hundred eight thousand, eight hundred thirteen".