7681305520 has 80 divisors (see below), whose sum is σ = 20566326528. Its totient is φ = 2613461760.

The previous prime is 7681305497. The next prime is 7681305557. The reversal of 7681305520 is 255031867.

It is a tau number, because it is divible by the number of its divisors (80).

It is a self number, because there is not a number n which added to its sum of digits gives 7681305520.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21007 + ... + 125713.

Almost surely, 2^7681305520 is an apocalyptic number.

7681305520 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 7681305520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10283163264).

7681305520 is an abundant number, since it is smaller than the sum of its proper divisors (12885021008).

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

7681305520 is a wasteful number, since it uses less digits than its factorization.

7681305520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 104858 (or 104852 counting only the distinct ones).

The product of its (nonzero) digits is 50400, while the sum is 37.

The square root of 7681305520 is about 87643.0574546552. The cubic root of 7681305520 is about 1973.0814478938.

The spelling of 7681305520 in words is "seven billion, six hundred eighty-one million, three hundred five thousand, five hundred twenty".