7681398913 has 8 divisors (see below), whose sum is σ = 7884230760. Its totient is φ = 7479304320.

The previous prime is 7681398889. The next prime is 7681398929. The reversal of 7681398913 is 3198931867.

It can be written as a sum of positive squares in 4 ways, for example, as 2627895169 + 5053503744 = 51263^2 + 71088^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7681398913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7681398313) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 163170 + ... + 204907.

It is an arithmetic number, because the mean of its divisors is an integer number (985528845).

Almost surely, 2^7681398913 is an apocalyptic number.

It is an amenable number.

7681398913 is a deficient number, since it is larger than the sum of its proper divisors (202831847).

7681398913 is a wasteful number, since it uses less digits than its factorization.

7681398913 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 368627.

The product of its digits is 1959552, while the sum is 55.

The square root of 7681398913 is about 87643.5902562190. The cubic root of 7681398913 is about 1973.0894444185.

The spelling of 7681398913 in words is "seven billion, six hundred eighty-one million, three hundred ninety-eight thousand, nine hundred thirteen".