6501405663 has 6 divisors (see below), whose sum is σ = 9390919304. Its totient is φ = 4334270436.

The previous prime is 6501405661. The next prime is 6501405721. The reversal of 6501405663 is 3665041056.

6501405663 is a `hidden beast` number, since 6 + 50 + 1 + 40 + 566 + 3 = 666.

It is not a de Polignac number, because 6501405663 - 2¹ = 6501405661 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6501405661) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 361189195 + ... + 361189212.

Almost surely, 2^6501405663 is an apocalyptic number.

6501405663 is a deficient number, since it is larger than the sum of its proper divisors (2889513641).

6501405663 is a wasteful number, since it uses less digits than its factorization.

6501405663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 722378413 (or 722378410 counting only the distinct ones).

The product of its (nonzero) digits is 64800, while the sum is 36.

The square root of 6501405663 is about 80631.2945635874. The cubic root of 6501405663 is about 1866.3900982719.

It can be divided in two parts, 6501 and 405663, that added together give a square (412164 = 642²).

The spelling of 6501405663 in words is "six billion, five hundred one million, four hundred five thousand, six hundred sixty-three".