18040551171889 has 3 divisors (see below), whose sum is σ = 18040555419307. Its totient is φ = 18040546924472.

The previous prime is 18040551171887. The next prime is 18040551171947. The reversal of 18040551171889 is 98817115504081.

It is a happy number.

The square root of 18040551171889 is 4247417.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 8881502634225 + 9159048537664 = 2980185^2 + 3026392^2 .

It is not a de Polignac number, because 18040551171889 - 2¹ = 18040551171887 is a prime.

It is a super-2 number, since 2×18040551171889² (a number of 27 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18040551171887) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 2123709 + ... + 6371125.

Almost surely, 2^{18040551171889} is an apocalyptic number.

18040551171889 is the 4247417-th square number.

18040551171889 is the 2123709-th centered octagonal number.

It is an amenable number.

18040551171889 is a deficient number, since it is larger than the sum of its proper divisors (4247418).

18040551171889 is an frugal number, since it uses more digits than its factorization.

18040551171889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8494834 (or 4247417 counting only the distinct ones).

The product of its (nonzero) digits is 3225600, while the sum is 58.

The spelling of 18040551171889 in words is "eighteen trillion, forty billion, five hundred fifty-one million, one hundred seventy-one thousand, eight hundred eighty-nine".