6503664857 has 4 divisors (see below), whose sum is σ = 6886233396. Its totient is φ = 6121096320.

The previous prime is 6503664847. The next prime is 6503664863. The reversal of 6503664857 is 7584663056.

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 4516377616 + 1987287241 = 67204^2 + 44579^2 .

It is a cyclic number.

It is not a de Polignac number, because 6503664857 - 2¹⁸ = 6503402713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6503664847) 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, 191284244 + ... + 191284277.

It is an arithmetic number, because the mean of its divisors is an integer number (1721558349).

Almost surely, 2^6503664857 is an apocalyptic number.

It is an amenable number.

6503664857 is a deficient number, since it is larger than the sum of its proper divisors (382568539).

6503664857 is a wasteful number, since it uses less digits than its factorization.

6503664857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 382568538.

The product of its (nonzero) digits is 3628800, while the sum is 50.

The square root of 6503664857 is about 80645.3027584372. The cubic root of 6503664857 is about 1866.6062591669.

The spelling of 6503664857 in words is "six billion, five hundred three million, six hundred sixty-four thousand, eight hundred fifty-seven".