2121165509 has 8 divisors (see below), whose sum is σ = 2130517248. Its totient is φ = 2111825520.

The previous prime is 2121165499. The next prime is 2121165511. The reversal of 2121165509 is 9055611212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2121165509 - 2⁸ = 2121165253 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121165559) 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 7 ways as a sum of consecutive naturals, for example, 715859 + ... + 718815.

It is an arithmetic number, because the mean of its divisors is an integer number (266314656).

Almost surely, 2^2121165509 is an apocalyptic number.

It is an amenable number.

2121165509 is a deficient number, since it is larger than the sum of its proper divisors (9351739).

2121165509 is a wasteful number, since it uses less digits than its factorization.

2121165509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5875.

The product of its (nonzero) digits is 5400, while the sum is 32.

The square root of 2121165509 is about 46056.1126127684. The cubic root of 2121165509 is about 1284.8670312128.

The spelling of 2121165509 in words is "two billion, one hundred twenty-one million, one hundred sixty-five thousand, five hundred nine".