9990388408 has 128 divisors (see below), whose sum is σ = 26018496000. Its totient is φ = 3468971520.

The previous prime is 9990388381. The next prime is 9990388409. The reversal of 9990388408 is 8048830999.

It is a super-4 number, since 4×9990388408⁴ (a number of 41 digits) contains 4444 as substring.

It is a Harshad number since it is a multiple of its sum of digits (58).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9990388409) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 210723 + ... + 253741.

It is an arithmetic number, because the mean of its divisors is an integer number (203269500).

Almost surely, 2^9990388408 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 9990388408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13009248000).

9990388408 is an abundant number, since it is smaller than the sum of its proper divisors (16028107592).

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

9990388408 is a wasteful number, since it uses less digits than its factorization.

9990388408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43085 (or 43081 counting only the distinct ones).

The product of its (nonzero) digits is 4478976, while the sum is 58.

The square root of 9990388408 is about 99951.9304866094. The cubic root of 9990388408 is about 2153.7442171921.

The spelling of 9990388408 in words is "nine billion, nine hundred ninety million, three hundred eighty-eight thousand, four hundred eight".