7909646640 has 240 divisors, whose sum is σ = 29764309248. Its totient is φ = 1729254912.

The previous prime is 7909646623. The next prime is 7909646669. The reversal of 7909646640 is 466469097.

It is a tau number, because it is divible by the number of its divisors (240).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 255859 + ... + 285101.

Almost surely, 2^7909646640 is an apocalyptic number.

7909646640 is a gapful number since it is divisible by the number (70) 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 7909646640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14882154624).

7909646640 is an abundant number, since it is smaller than the sum of its proper divisors (21854662608).

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

7909646640 is a wasteful number, since it uses less digits than its factorization.

7909646640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29296 (or 29283 counting only the distinct ones).

The product of its (nonzero) digits is 1959552, while the sum is 51.

The square root of 7909646640 is about 88936.1942068582. The cubic root of 7909646640 is about 1992.4420278395.

The spelling of 7909646640 in words is "seven billion, nine hundred nine million, six hundred forty-six thousand, six hundred forty".