63865816539 has 48 divisors (see below), whose sum is σ = 100796691456. Its totient is φ = 35855265600.

The previous prime is 63865816537. The next prime is 63865816549. The reversal of 63865816539 is 93561856836.

It is a happy number.

It is not a de Polignac number, because 63865816539 - 2¹ = 63865816537 is a prime.

It is not an unprimeable number, because it can be changed into a prime (63865816537) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 8882704 + ... + 8889890.

It is an arithmetic number, because the mean of its divisors is an integer number (2099931072).

Almost surely, 2^63865816539 is an apocalyptic number.

63865816539 is a deficient number, since it is larger than the sum of its proper divisors (36930874917).

63865816539 is a wasteful number, since it uses less digits than its factorization.

63865816539 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8256 (or 8249 counting only the distinct ones).

The product of its digits is 27993600, while the sum is 60.

The spelling of 63865816539 in words is "sixty-three billion, eight hundred sixty-five million, eight hundred sixteen thousand, five hundred thirty-nine".