18660155665 has 8 divisors (see below), whose sum is σ = 22488292008. Its totient is φ = 14864054400.

The previous prime is 18660155663. The next prime is 18660155707. The reversal of 18660155665 is 56655106681.

It can be written as a sum of positive squares in 4 ways, for example, as 2648543296 + 16011612369 = 51464^2 + 126537^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 18660155665 - 2¹ = 18660155663 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18660155663) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8007486 + ... + 8009815.

It is an arithmetic number, because the mean of its divisors is an integer number (2811036501).

Almost surely, 2^18660155665 is an apocalyptic number.

It is an amenable number.

18660155665 is a deficient number, since it is larger than the sum of its proper divisors (3828136343).

18660155665 is a wasteful number, since it uses less digits than its factorization.

18660155665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16017539.

The product of its (nonzero) digits is 1296000, while the sum is 49.

The spelling of 18660155665 in words is "eighteen billion, six hundred sixty million, one hundred fifty-five thousand, six hundred sixty-five".