11185389121 has 3 divisors (see below), whose sum is σ = 11185494883. Its totient is φ = 11185283360.

The previous prime is 11185389113. The next prime is 11185389151. The reversal of 11185389121 is 12198358111.

The square root of 11185389121 is 105761.

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, and also an emirpimes, since its reverse is a distinct semiprime: 12198358111 = 367 ⋅33238033.

It can be written as a sum of positive squares in only one way, i.e., 177182721 + 11008206400 = 13311^2 + 104920^2 .

It is not a de Polignac number, because 11185389121 - 2³ = 11185389113 is a prime.

It is a super-2 number, since 2×11185389121² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (40) 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 (11185389151) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 52881 + ... + 158641.

Almost surely, 2^11185389121 is an apocalyptic number.

11185389121 is the 105761-st square number.

11185389121 is the 52881-st centered octagonal number.

It is an amenable number.

11185389121 is a deficient number, since it is larger than the sum of its proper divisors (105762).

11185389121 is an frugal number, since it uses more digits than its factorization.

11185389121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 211522 (or 105761 counting only the distinct ones).

The product of its digits is 17280, while the sum is 40.

The spelling of 11185389121 in words is "eleven billion, one hundred eighty-five million, three hundred eighty-nine thousand, one hundred twenty-one".