217123977994 has 64 divisors (see below), whose sum is σ = 411999436800. Its totient is φ = 83363273280.

The previous prime is 217123977949. The next prime is 217123978007. The reversal of 217123977994 is 499779321712.

217123977994 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2876889 + ... + 2951395.

It is an arithmetic number, because the mean of its divisors is an integer number (6437491200).

Almost surely, 2^217123977994 is an apocalyptic number.

217123977994 is a deficient number, since it is larger than the sum of its proper divisors (194875458806).

217123977994 is a wasteful number, since it uses less digits than its factorization.

217123977994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74803.

The product of its digits is 12002256, while the sum is 61.

The spelling of 217123977994 in words is "two hundred seventeen billion, one hundred twenty-three million, nine hundred seventy-seven thousand, nine hundred ninety-four".