66660615109 has 32 divisors (see below), whose sum is σ = 76060131840. Its totient is φ = 57891153600.

The previous prime is 66660615107. The next prime is 66660615137. The reversal of 66660615109 is 90151606666.

It is a cyclic number.

It is not a de Polignac number, because 66660615109 - 2¹ = 66660615107 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66660615107) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5158234 + ... + 5171140.

It is an arithmetic number, because the mean of its divisors is an integer number (2376879120).

Almost surely, 2^66660615109 is an apocalyptic number.

It is an amenable number.

66660615109 is a deficient number, since it is larger than the sum of its proper divisors (9399516731).

66660615109 is a wasteful number, since it uses less digits than its factorization.

66660615109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13201.

The product of its (nonzero) digits is 349920, while the sum is 46.

The spelling of 66660615109 in words is "sixty-six billion, six hundred sixty million, six hundred fifteen thousand, one hundred nine".