18166081655 has 8 divisors (see below), whose sum is σ = 22106330784. Its totient is φ = 14328176800.

The previous prime is 18166081643. The next prime is 18166081667. The reversal of 18166081655 is 55618066181.

It is an interprime number because it is at equal distance from previous prime (18166081643) and next prime (18166081667).

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

It is not a de Polignac number, because 18166081655 - 2¹⁴ = 18166065271 is a prime.

It is a super-2 number, since 2×18166081655² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25585676 + ... + 25586385.

It is an arithmetic number, because the mean of its divisors is an integer number (2763291348).

Almost surely, 2^18166081655 is an apocalyptic number.

18166081655 is a deficient number, since it is larger than the sum of its proper divisors (3940249129).

18166081655 is an equidigital number, since it uses as much as digits as its factorization.

18166081655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51172137.

The product of its (nonzero) digits is 345600, while the sum is 47.

The spelling of 18166081655 in words is "eighteen billion, one hundred sixty-six million, eighty-one thousand, six hundred fifty-five".