6427649664 has 48 divisors (see below), whose sum is σ = 18496234770. Its totient is φ = 2142549504.

The previous prime is 6427649651. The next prime is 6427649671. The reversal of 6427649664 is 4669467246.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 6027969600 + 399680064 = 77640^2 + 19992^2 .

It is a tau number, because it is divible by the number of its divisors (48).

It is a self number, because there is not a number n which added to its sum of digits gives 6427649664.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2788627 + ... + 2790930.

Almost surely, 2^6427649664 is an apocalyptic number.

6427649664 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

6427649664 is an abundant number, since it is smaller than the sum of its proper divisors (12068585106).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6427649664 is a wasteful number, since it uses less digits than its factorization.

6427649664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5579577 (or 5579562 counting only the distinct ones).

The product of its digits is 10450944, while the sum is 54.

The square root of 6427649664 is about 80172.6241556306. The cubic root of 6427649664 is about 1859.3054083538.

The spelling of 6427649664 in words is "six billion, four hundred twenty-seven million, six hundred forty-nine thousand, six hundred sixty-four".