999978772 has 48 divisors (see below), whose sum is σ = 1938650112. Its totient is φ = 448456320.

The previous prime is 999978767. The next prime is 999978773. The reversal of 999978772 is 277879999.

It is a junction number, because it is equal to n+sod(n) for n = 999978698 and 999978707.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999978773) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 293197 + ... + 296587.

It is an arithmetic number, because the mean of its divisors is an integer number (40388544).

Almost surely, 2^999978772 is an apocalyptic number.

It is an amenable number.

999978772 is a deficient number, since it is larger than the sum of its proper divisors (938671340).

999978772 is a wasteful number, since it uses less digits than its factorization.

999978772 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3568 (or 3566 counting only the distinct ones).

The product of its digits is 36006768, while the sum is 67.

The square root of 999978772 is about 31622.4409557517. The cubic root of 999978772 is about 999.9929239499.

The spelling of 999978772 in words is "nine hundred ninety-nine million, nine hundred seventy-eight thousand, seven hundred seventy-two".