63868991265 has 56 divisors (see below), whose sum is σ = 115419331008. Its totient is φ = 33912963360.

The previous prime is 63868991239. The next prime is 63868991267. The reversal of 63868991265 is 56219986836.

It is not a de Polignac number, because 63868991265 - 2⁸ = 63868991009 is a prime.

It is not an unprimeable number, because it can be changed into a prime (63868991267) by changing a digit.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 788820 + ... + 866010.

Almost surely, 2^63868991265 is an apocalyptic number.

It is an amenable number.

63868991265 is a deficient number, since it is larger than the sum of its proper divisors (51550339743).

63868991265 is an equidigital number, since it uses as much as digits as its factorization.

63868991265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77441 (or 77426 counting only the distinct ones).

The product of its digits is 33592320, while the sum is 63.

The spelling of 63868991265 in words is "sixty-three billion, eight hundred sixty-eight million, nine hundred ninety-one thousand, two hundred sixty-five".