18665491071 has 32 divisors (see below), whose sum is σ = 26736030720. Its totient is φ = 11541712896.

The previous prime is 18665491069. The next prime is 18665491133. The reversal of 18665491071 is 17019456681.

It is a happy number.

It is not a de Polignac number, because 18665491071 - 2¹ = 18665491069 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18665491071.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18665491571) 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, 1174440 + ... + 1190226.

It is an arithmetic number, because the mean of its divisors is an integer number (835500960).

Almost surely, 2^18665491071 is an apocalyptic number.

18665491071 is a deficient number, since it is larger than the sum of its proper divisors (8070539649).

18665491071 is a wasteful number, since it uses less digits than its factorization.

18665491071 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16143.

The product of its (nonzero) digits is 362880, while the sum is 48.

The spelling of 18665491071 in words is "eighteen billion, six hundred sixty-five million, four hundred ninety-one thousand, seventy-one".