9780400 has 90 divisors (see below), whose sum is σ = 27388500. Its totient is φ = 3346560.

The previous prime is 9780377. The next prime is 9780403. The reversal of 9780400 is 40879.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (9780403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 19351 + ... + 19849.

Almost surely, 2^9780400 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 9780400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13694250).

9780400 is an abundant number, since it is smaller than the sum of its proper divisors (17608100).

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

9780400 is a wasteful number, since it uses less digits than its factorization.

9780400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 531 (or 513 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 28.

The square root of 9780400 is about 3127.3631065164. The cubic root of 9780400 is about 213.8547358998.

The spelling of 9780400 in words is "nine million, seven hundred eighty thousand, four hundred".