6450644664 has 24 divisors (see below), whose sum is σ = 17470496160. Its totient is φ = 2150214864.

The previous prime is 6450644573. The next prime is 6450644687. The reversal of 6450644664 is 4664460546.

It is a tau number, because it is divible by the number of its divisors (24).

It is a super-2 number, since 2×6450644664² = 83221633162383345792, which contains 22 as substring.

It is a congruent number.

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, 44796072 + ... + 44796215.

It is an arithmetic number, because the mean of its divisors is an integer number (727937340).

Almost surely, 2^6450644664 is an apocalyptic number.

It is an amenable number.

6450644664 is an abundant number, since it is smaller than the sum of its proper divisors (11019851496).

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

6450644664 is a wasteful number, since it uses less digits than its factorization.

6450644664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89592299 (or 89592292 counting only the distinct ones).

The product of its (nonzero) digits is 1658880, while the sum is 45.

The square root of 6450644664 is about 80315.9054235212. The cubic root of 6450644664 is about 1861.5199992743.

The spelling of 6450644664 in words is "six billion, four hundred fifty million, six hundred forty-four thousand, six hundred sixty-four".