2315521821 has 16 divisors (see below), whose sum is σ = 3143389760. Its totient is φ = 1515853440.

The previous prime is 2315521783. The next prime is 2315521829. The reversal of 2315521821 is 1281255132.

It is not a de Polignac number, because 2315521821 - 2¹⁸ = 2315259677 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 (2315521829) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27066 + ... + 73236.

It is an arithmetic number, because the mean of its divisors is an integer number (196461860).

Almost surely, 2^2315521821 is an apocalyptic number.

It is an amenable number.

2315521821 is a deficient number, since it is larger than the sum of its proper divisors (827867939).

2315521821 is a wasteful number, since it uses less digits than its factorization.

2315521821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46476.

The product of its digits is 4800, while the sum is 30.

The square root of 2315521821 is about 48119.8692953337. The cubic root of 2315521821 is about 1322.9688725480.

Adding to 2315521821 its reverse (1281255132), we get a palindrome (3596776953).

The spelling of 2315521821 in words is "two billion, three hundred fifteen million, five hundred twenty-one thousand, eight hundred twenty-one".