2016231521 has 4 divisors (see below), whose sum is σ = 2059130112. Its totient is φ = 1973332932.

The previous prime is 2016231509. The next prime is 2016231551. The reversal of 2016231521 is 1251326102.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2016231521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2016231551) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21449225 + ... + 21449318.

It is an arithmetic number, because the mean of its divisors is an integer number (514782528).

Almost surely, 2^2016231521 is an apocalyptic number.

It is an amenable number.

2016231521 is a deficient number, since it is larger than the sum of its proper divisors (42898591).

2016231521 is an equidigital number, since it uses as much as digits as its factorization.

2016231521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42898590.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 2016231521 is about 44902.4667585201. The cubic root of 2016231521 is about 1263.3202764729.

Adding to 2016231521 its reverse (1251326102), we get a palindrome (3267557623).

The spelling of 2016231521 in words is "two billion, sixteen million, two hundred thirty-one thousand, five hundred twenty-one".