9919724400 has 480 divisors, whose sum is σ = 37836953280. Its totient is φ = 2459566080.

The previous prime is 9919724359. The next prime is 9919724429. The reversal of 9919724400 is 44279199.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 17808922 + ... + 17809478.

It is an arithmetic number, because the mean of its divisors is an integer number (78826986).

Almost surely, 2^9919724400 is an apocalyptic number.

9919724400 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 9919724400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18918476640).

9919724400 is an abundant number, since it is smaller than the sum of its proper divisors (27917228880).

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

9919724400 is a wasteful number, since it uses less digits than its factorization.

9919724400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 698 (or 681 counting only the distinct ones).

The product of its (nonzero) digits is 163296, while the sum is 45.

The square root of 9919724400 is about 99597.8132290062. The cubic root of 9919724400 is about 2148.6542434538.

The spelling of 9919724400 in words is "nine billion, nine hundred nineteen million, seven hundred twenty-four thousand, four hundred".