647646781513 has 8 divisors (see below), whose sum is σ = 655572657600. Its totient is φ = 639755592720.

The previous prime is 647646781501. The next prime is 647646781541. The reversal of 647646781513 is 315187646746.

It is a happy number.

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-647646781513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (647646781543) 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, 8634253 + ... + 8708938.

It is an arithmetic number, because the mean of its divisors is an integer number (81946582200).

Almost surely, 2^647646781513 is an apocalyptic number.

It is an amenable number.

647646781513 is a deficient number, since it is larger than the sum of its proper divisors (7925876087).

647646781513 is a wasteful number, since it uses less digits than its factorization.

647646781513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17343647.

The product of its digits is 20321280, while the sum is 58.

The spelling of 647646781513 in words is "six hundred forty-seven billion, six hundred forty-six million, seven hundred eighty-one thousand, five hundred thirteen".