63934657817 has 4 divisors (see below), whose sum is σ = 66139301220. Its totient is φ = 61730014416.

The previous prime is 63934657811. The next prime is 63934657819. The reversal of 63934657817 is 71875643936.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 51301797001 + 12632860816 = 226499^2 + 112396^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-63934657817 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (63934657811) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1102321658 + ... + 1102321715.

It is an arithmetic number, because the mean of its divisors is an integer number (16534825305).

Almost surely, 2^63934657817 is an apocalyptic number.

It is an amenable number.

63934657817 is a deficient number, since it is larger than the sum of its proper divisors (2204643403).

63934657817 is a wasteful number, since it uses less digits than its factorization.

63934657817 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2204643402.

The product of its digits is 22861440, while the sum is 59.

The spelling of 63934657817 in words is "sixty-three billion, nine hundred thirty-four million, six hundred fifty-seven thousand, eight hundred seventeen".