99978966 has 12 divisors (see below), whose sum is σ = 216621132. Its totient is φ = 33326316.

The previous prime is 99978959. The next prime is 99978971. The reversal of 99978966 is 66987999.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2777176 + ... + 2777211.

It is an arithmetic number, because the mean of its divisors is an integer number (18051761).

Almost surely, 2^99978966 is an apocalyptic number.

99978966 is an abundant number, since it is smaller than the sum of its proper divisors (116642166).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

99978966 is a wasteful number, since it uses less digits than its factorization.

99978966 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5554395 (or 5554392 counting only the distinct ones).

The product of its digits is 13226976, while the sum is 63.

The square root of 99978966 is about 9998.9482446905. The cubic root of 99978966 is about 464.1263373528.

The spelling of 99978966 in words is "ninety-nine million, nine hundred seventy-eight thousand, nine hundred sixty-six".