6516065521666 has 4 divisors (see below), whose sum is σ = 9774098282502. Its totient is φ = 3258032760832.

The previous prime is 6516065521627. The next prime is 6516065521681. The reversal of 6516065521666 is 6661255606156.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 3639971752641 + 2876093769025 = 1907871^2 + 1695905^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1629016380415 + ... + 1629016380418.

Almost surely, 2^{6516065521666} is an apocalyptic number.

6516065521666 is a deficient number, since it is larger than the sum of its proper divisors (3258032760836).

6516065521666 is a wasteful number, since it uses less digits than its factorization.

6516065521666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3258032760835.

The product of its (nonzero) digits is 11664000, while the sum is 55.

The spelling of 6516065521666 in words is "six trillion, five hundred sixteen billion, sixty-five million, five hundred twenty-one thousand, six hundred sixty-six".