121359566689 has 3 divisors (see below), whose sum is σ = 121359915057. Its totient is φ = 121359218322.

The previous prime is 121359566687. The next prime is 121359566707. The reversal of 121359566689 is 986665953121.

The square root of 121359566689 is 348367.

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: 986665953121 = 17 ⋅58039173713.

It is not a de Polignac number, because 121359566689 - 2¹ = 121359566687 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121359566681) 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, 174184 + ... + 522550.

It is an arithmetic number, because the mean of its divisors is an integer number (40453305019).

Almost surely, 2^121359566689 is an apocalyptic number.

121359566689 is the 348367-th square number.

121359566689 is the 174184-th centered octagonal number.

It is an amenable number.

121359566689 is a deficient number, since it is larger than the sum of its proper divisors (348368).

121359566689 is an frugal number, since it uses more digits than its factorization.

121359566689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 696734 (or 348367 counting only the distinct ones).

The product of its digits is 20995200, while the sum is 61.

The spelling of 121359566689 in words is "one hundred twenty-one billion, three hundred fifty-nine million, five hundred sixty-six thousand, six hundred eighty-nine".