989936640 has 880 divisors, whose sum is σ = 4565366784. Its totient is φ = 199065600.

The previous prime is 989936627. The next prime is 989936641. The reversal of 989936640 is 46639989.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (880).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (989936641) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 31933425 + ... + 31933455.

Almost surely, 2^989936640 is an apocalyptic number.

989936640 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 989936640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2282683392).

989936640 is an abundant number, since it is smaller than the sum of its proper divisors (3575430144).

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

989936640 is a wasteful number, since it uses less digits than its factorization.

989936640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86 (or 59 counting only the distinct ones).

The product of its (nonzero) digits is 2519424, while the sum is 54.

The square root of 989936640 is about 31463.2585725001. The cubic root of 989936640 is about 996.6342309751.

The spelling of 989936640 in words is "nine hundred eighty-nine million, nine hundred thirty-six thousand, six hundred forty".