66515772556 has 24 divisors (see below), whose sum is σ = 120112107696. Its totient is φ = 32209870080.

The previous prime is 66515772523. The next prime is 66515772563. The reversal of 66515772556 is 65527751566.

66515772556 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 66515772497 and 66515772506.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1457766 + ... + 1502701.

It is an arithmetic number, because the mean of its divisors is an integer number (5004671154).

Almost surely, 2^66515772556 is an apocalyptic number.

It is an amenable number.

66515772556 is a deficient number, since it is larger than the sum of its proper divisors (53596335140).

66515772556 is a wasteful number, since it uses less digits than its factorization.

66515772556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2960649 (or 2960647 counting only the distinct ones).

The product of its digits is 13230000, while the sum is 55.

The spelling of 66515772556 in words is "sixty-six billion, five hundred fifteen million, seven hundred seventy-two thousand, five hundred fifty-six".