978720400 has 120 divisors (see below), whose sum is σ = 2828876480. Its totient is φ = 317882880.

The previous prime is 978720383. The next prime is 978720409. The reversal of 978720400 is 4027879.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 978720400.

It is not an unprimeable number, because it can be changed into a prime (978720409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 44002 + ... + 62398.

Almost surely, 2^978720400 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 978720400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1414438240).

978720400 is an abundant number, since it is smaller than the sum of its proper divisors (1850156080).

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

978720400 is a wasteful number, since it uses less digits than its factorization.

978720400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18441 (or 18430 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 37.

The square root of 978720400 is about 31284.5073478871. The cubic root of 978720400 is about 992.8558831357.

The spelling of 978720400 in words is "nine hundred seventy-eight million, seven hundred twenty thousand, four hundred".