997717635866 has 32 divisors (see below), whose sum is σ = 1838012902272. Its totient is φ = 396434142720.

The previous prime is 997717635851. The next prime is 997717635949. The reversal of 997717635866 is 668536717799.

997717635866 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 997717635793 and 997717635802.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31268315 + ... + 31300206.

It is an arithmetic number, because the mean of its divisors is an integer number (57437903196).

Almost surely, 2^997717635866 is an apocalyptic number.

997717635866 is a deficient number, since it is larger than the sum of its proper divisors (840295266406).

997717635866 is a wasteful number, since it uses less digits than its factorization.

997717635866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62568614.

The product of its digits is 720135360, while the sum is 74.

The spelling of 997717635866 in words is "nine hundred ninety-seven billion, seven hundred seventeen million, six hundred thirty-five thousand, eight hundred sixty-six".