8013781709 has 8 divisors (see below), whose sum is σ = 8080416120. Its totient is φ = 7947265536.

The previous prime is 8013781703. The next prime is 8013781723. The reversal of 8013781709 is 9071873108.

It can be written as a sum of positive squares in 4 ways, for example, as 124434025 + 7889347684 = 11155^2 + 88822^2 .

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-8013781709 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 8013781709.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8013781703) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 109247 + ... + 167219.

It is an arithmetic number, because the mean of its divisors is an integer number (1010052015).

Almost surely, 2^8013781709 is an apocalyptic number.

It is an amenable number.

8013781709 is a deficient number, since it is larger than the sum of its proper divisors (66634411).

8013781709 is a wasteful number, since it uses less digits than its factorization.

8013781709 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59119.

The product of its (nonzero) digits is 84672, while the sum is 44.

The square root of 8013781709 is about 89519.7280435994. The cubic root of 8013781709 is about 2001.1478168822.

The spelling of 8013781709 in words is "eight billion, thirteen million, seven hundred eighty-one thousand, seven hundred nine".