17988442641 has 81 divisors (see below), whose sum is σ = 29859502257. Its totient is φ = 10429248960.

The previous prime is 17988442639. The next prime is 17988442649. The reversal of 17988442641 is 14624488971.

The square root of 17988442641 is 134121.

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

17988442641 is a `hidden beast` number, since 17 + 98 + 84 + 426 + 41 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 13854467025 + 4133975616 = 117705^2 + 64296^2 .

It is not a de Polignac number, because 17988442641 - 2¹ = 17988442639 is a prime.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

Its product of digits (3096576) is a multiple of the sum of its prime divisors (216).

It is not an unprimeable number, because it can be changed into a prime (17988442649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 99383571 + ... + 99383751.

Almost surely, 2^17988442641 is an apocalyptic number.

17988442641 is the 134121-st square number.

17988442641 is the 67061-st centered octagonal number.

It is an amenable number.

17988442641 is a deficient number, since it is larger than the sum of its proper divisors (11871059616).

17988442641 is a wasteful number, since it uses less digits than its factorization.

17988442641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 432 (or 216 counting only the distinct ones).

The product of its digits is 3096576, while the sum is 54.

The spelling of 17988442641 in words is "seventeen billion, nine hundred eighty-eight million, four hundred forty-two thousand, six hundred forty-one".