66400796863 has 4 divisors (see below), whose sum is σ = 66401312728. Its totient is φ = 66400281000.

The previous prime is 66400796851. The next prime is 66400796899. The reversal of 66400796863 is 36869700466.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 36869700466 = 2 ⋅18434850233.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66400796863 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 (66400796963) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 111988 + ... + 381238.

It is an arithmetic number, because the mean of its divisors is an integer number (16600328182).

Almost surely, 2^66400796863 is an apocalyptic number.

66400796863 is a deficient number, since it is larger than the sum of its proper divisors (515865).

66400796863 is a wasteful number, since it uses less digits than its factorization.

66400796863 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 515864.

The product of its (nonzero) digits is 7838208, while the sum is 55.

The spelling of 66400796863 in words is "sixty-six billion, four hundred million, seven hundred ninety-six thousand, eight hundred sixty-three".