6991501440 has 768 divisors, whose sum is σ = 29547555840. Its totient is φ = 1365811200.

The previous prime is 6991501423. The next prime is 6991501441. The reversal of 6991501440 is 441051996.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6991501441) 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 95 ways as a sum of consecutive naturals, for example, 53370175 + ... + 53370305.

It is an arithmetic number, because the mean of its divisors is an integer number (38473380).

Almost surely, 2^6991501440 is an apocalyptic number.

6991501440 is a gapful number since it is divisible by the number (60) 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 6991501440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14773777920).

6991501440 is an abundant number, since it is smaller than the sum of its proper divisors (22556054400).

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

6991501440 is a wasteful number, since it uses less digits than its factorization.

6991501440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 209 (or 178 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 39.

The square root of 6991501440 is about 83615.1986184330. The cubic root of 6991501440 is about 1912.1567187706.

The spelling of 6991501440 in words is "six billion, nine hundred ninety-one million, five hundred one thousand, four hundred forty".