2121531265 has 48 divisors (see below), whose sum is σ = 3019026816. Its totient is φ = 1401845760.

The previous prime is 2121531233. The next prime is 2121531287. The reversal of 2121531265 is 5621351212.

It is not a de Polignac number, because 2121531265 - 2⁵ = 2121531233 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 6295177 + ... + 6295513.

It is an arithmetic number, because the mean of its divisors is an integer number (62896392).

Almost surely, 2^2121531265 is an apocalyptic number.

It is an amenable number.

2121531265 is a deficient number, since it is larger than the sum of its proper divisors (897495551).

2121531265 is a wasteful number, since it uses less digits than its factorization.

2121531265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 538 (or 497 counting only the distinct ones).

The product of its digits is 3600, while the sum is 28.

The square root of 2121531265 is about 46060.0832066118. The cubic root of 2121531265 is about 1284.9408775354.

Adding to 2121531265 its reverse (5621351212), we get a palindrome (7742882477).

The spelling of 2121531265 in words is "two billion, one hundred twenty-one million, five hundred thirty-one thousand, two hundred sixty-five".