213521421241 has 24 divisors (see below), whose sum is σ = 234091657800. Its totient is φ = 194495454720.

The previous prime is 213521421199. The next prime is 213521421257. The reversal of 213521421241 is 142124125312.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 120631182400 + 92890238841 = 347320^2 + 304779^2 .

It is not a de Polignac number, because 213521421241 - 2²³ = 213513032633 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (213521401241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2480715 + ... + 2565343.

It is an arithmetic number, because the mean of its divisors is an integer number (9753819075).

Almost surely, 2^213521421241 is an apocalyptic number.

It is an amenable number.

213521421241 is a deficient number, since it is larger than the sum of its proper divisors (20570236559).

213521421241 is a wasteful number, since it uses less digits than its factorization.

213521421241 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84937 (or 84918 counting only the distinct ones).

The product of its digits is 3840, while the sum is 28.

Adding to 213521421241 its reverse (142124125312), we get a palindrome (355645546553).

The spelling of 213521421241 in words is "two hundred thirteen billion, five hundred twenty-one million, four hundred twenty-one thousand, two hundred forty-one".