17581020121 has 12 divisors (see below), whose sum is σ = 20462223888. Its totient is φ = 15061463592.

The previous prime is 17581020109. The next prime is 17581020139. The reversal of 17581020121 is 12102018571.

It is not a de Polignac number, because 17581020121 - 2⁷ = 17581019993 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 17581020121.

It is not an unprimeable number, because it can be changed into a prime (17581020151) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 631 + ... + 187516.

It is an arithmetic number, because the mean of its divisors is an integer number (1705185324).

Almost surely, 2^17581020121 is an apocalyptic number.

It is an amenable number.

17581020121 is a deficient number, since it is larger than the sum of its proper divisors (2881203767).

17581020121 is a wasteful number, since it uses less digits than its factorization.

17581020121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 190068 (or 190061 counting only the distinct ones).

The product of its (nonzero) digits is 1120, while the sum is 28.

Adding to 17581020121 its reverse (12102018571), we get a palindrome (29683038692).

The spelling of 17581020121 in words is "seventeen billion, five hundred eighty-one million, twenty thousand, one hundred twenty-one".