66643362651 has 16 divisors (see below), whose sum is σ = 95275699200. Its totient is φ = 41286131328.

The previous prime is 66643362637. The next prime is 66643362659. The reversal of 66643362651 is 15626334666.

It is not a de Polignac number, because 66643362651 - 2⁶ = 66643362587 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66643362651.

It is not an unprimeable number, because it can be changed into a prime (66643362659) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8266431 + ... + 8274488.

It is an arithmetic number, because the mean of its divisors is an integer number (5954731200).

Almost surely, 2^66643362651 is an apocalyptic number.

66643362651 is a deficient number, since it is larger than the sum of its proper divisors (28632336549).

66643362651 is a wasteful number, since it uses less digits than its factorization.

66643362651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16541018.

The product of its digits is 2799360, while the sum is 48.

The spelling of 66643362651 in words is "sixty-six billion, six hundred forty-three million, three hundred sixty-two thousand, six hundred fifty-one".