9966778 has 16 divisors (see below), whose sum is σ = 15552000. Its totient is φ = 4784752.

The previous prime is 9966769. The next prime is 9966791. The reversal of 9966778 is 8776699.

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, 13503 + ... + 14221.

It is an arithmetic number, because the mean of its divisors is an integer number (972000).

Almost surely, 2^9966778 is an apocalyptic number.

9966778 is a deficient number, since it is larger than the sum of its proper divisors (5585222).

9966778 is a wasteful number, since it uses less digits than its factorization.

9966778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 989.

The product of its digits is 1143072, while the sum is 52.

The square root of 9966778 is about 3157.0204307226. The cubic root of 9966778 is about 215.2046222111.

The spelling of 9966778 in words is "nine million, nine hundred sixty-six thousand, seven hundred seventy-eight".