66515644455 has 48 divisors (see below), whose sum is σ = 115299697536. Its totient is φ = 32729573760.

The previous prime is 66515644453. The next prime is 66515644487. The reversal of 66515644455 is 55444651566.

66515644455 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 66515644455 - 2¹ = 66515644453 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66515644398 and 66515644407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66515644451) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 6106444 + ... + 6117326.

It is an arithmetic number, because the mean of its divisors is an integer number (2402077032).

Almost surely, 2^66515644455 is an apocalyptic number.

66515644455 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

66515644455 is a deficient number, since it is larger than the sum of its proper divisors (48784053081).

66515644455 is a wasteful number, since it uses less digits than its factorization.

66515644455 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13328 (or 13315 counting only the distinct ones).

The product of its digits is 8640000, while the sum is 51.

The spelling of 66515644455 in words is "sixty-six billion, five hundred fifteen million, six hundred forty-four thousand, four hundred fifty-five".