917811494978 has 16 divisors (see below), whose sum is σ = 1573517799744. Its totient is φ = 393316117200.

The previous prime is 917811494891. The next prime is 917811494981. The reversal of 917811494978 is 879494118719.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2458325 + ... + 2806952.

It is an arithmetic number, because the mean of its divisors is an integer number (98344862484).

Almost surely, 2^917811494978 is an apocalyptic number.

917811494978 is a deficient number, since it is larger than the sum of its proper divisors (655706304766).

917811494978 is a wasteful number, since it uses less digits than its factorization.

917811494978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5277737.

The product of its digits is 36578304, while the sum is 68.

The spelling of 917811494978 in words is "nine hundred seventeen billion, eight hundred eleven million, four hundred ninety-four thousand, nine hundred seventy-eight".