6485561668 has 6 divisors (see below), whose sum is σ = 11349732926. Its totient is φ = 3242780832.

The previous prime is 6485561639. The next prime is 6485561681. The reversal of 6485561668 is 8661655846.

It can be written as a sum of positive squares in only one way, i.e., 6242264064 + 243297604 = 79008^2 + 15598^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 810695205 + ... + 810695212.

Almost surely, 2^6485561668 is an apocalyptic number.

It is an amenable number.

6485561668 is a deficient number, since it is larger than the sum of its proper divisors (4864171258).

6485561668 is a wasteful number, since it uses less digits than its factorization.

6485561668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1621390421 (or 1621390419 counting only the distinct ones).

The product of its digits is 8294400, while the sum is 55.

The square root of 6485561668 is about 80532.9849688933. The cubic root of 6485561668 is about 1864.8727274565.

The spelling of 6485561668 in words is "six billion, four hundred eighty-five million, five hundred sixty-one thousand, six hundred sixty-eight".