66893597986 has 4 divisors (see below), whose sum is σ = 100340396982. Its totient is φ = 33446798992.

The previous prime is 66893597957. The next prime is 66893597987. The reversal of 66893597986 is 68979539866.

66893597986 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 68979539866 = 2 ⋅34489769933.

It can be written as a sum of positive squares in only one way, i.e., 50645252025 + 16248345961 = 225045^2 + 127469^2 .

It is not an unprimeable number, because it can be changed into a prime (66893597987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16723399495 + ... + 16723399498.

Almost surely, 2^66893597986 is an apocalyptic number.

66893597986 is a deficient number, since it is larger than the sum of its proper divisors (33446798996).

66893597986 is a wasteful number, since it uses less digits than its factorization.

66893597986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33446798995.

The product of its digits is 1058158080, while the sum is 76.

The spelling of 66893597986 in words is "sixty-six billion, eight hundred ninety-three million, five hundred ninety-seven thousand, nine hundred eighty-six".