9978900 has 144 divisors (see below), whose sum is σ = 31664640. Its totient is φ = 2419200.

The previous prime is 9978889. The next prime is 9978911. The reversal of 9978900 is 98799.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (9978889) and next prime (9978911).

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors.

It is an Ulam number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 269682 + ... + 269718.

Almost surely, 2^9978900 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 9978900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15832320).

9978900 is an abundant number, since it is smaller than the sum of its proper divisors (21685740).

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

9978900 is a wasteful number, since it uses less digits than its factorization.

9978900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114 (or 107 counting only the distinct ones).

The product of its (nonzero) digits is 40824, while the sum is 42.

The square root of 9978900 is about 3158.9396955308. The cubic root of 9978900 is about 215.2918337298.

It can be divided in two parts, 9978 and 900, that added together give a triangular number (10878 = T₁₄₇).

The spelling of 9978900 in words is "nine million, nine hundred seventy-eight thousand, nine hundred".