6551566564 has 6 divisors (see below), whose sum is σ = 11465241494. Its totient is φ = 3275783280.

The previous prime is 6551566561. The next prime is 6551566601. The reversal of 6551566564 is 4656651556.

It can be written as a sum of positive squares in only one way, i.e., 5489328100 + 1062238464 = 74090^2 + 32592^2 .

It is not an unprimeable number, because it can be changed into a prime (6551566561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 818945817 + ... + 818945824.

Almost surely, 2^6551566564 is an apocalyptic number.

It is an amenable number.

6551566564 is a deficient number, since it is larger than the sum of its proper divisors (4913674930).

6551566564 is a wasteful number, since it uses less digits than its factorization.

6551566564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1637891645 (or 1637891643 counting only the distinct ones).

The product of its digits is 3240000, while the sum is 49.

The square root of 6551566564 is about 80941.7479672882. The cubic root of 6551566564 is about 1871.1777841623.

The spelling of 6551566564 in words is "six billion, five hundred fifty-one million, five hundred sixty-six thousand, five hundred sixty-four".