21520530204241 has 4 divisors (see below), whose sum is σ = 21614506318900. Its totient is φ = 21426554089584.

The previous prime is 21520530204197. The next prime is 21520530204269. The reversal of 21520530204241 is 14240203502512.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 14311815345216 + 7208714859025 = 3783096^2 + 2684905^2 .

It is a cyclic number.

It is not a de Polignac number, because 21520530204241 - 2¹⁵ = 21520530171473 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21520530204841) 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, 46988056986 + ... + 46988057443.

It is an arithmetic number, because the mean of its divisors is an integer number (5403626579725).

Almost surely, 2^{21520530204241} is an apocalyptic number.

It is an amenable number.

21520530204241 is a deficient number, since it is larger than the sum of its proper divisors (93976114659).

21520530204241 is an equidigital number, since it uses as much as digits as its factorization.

21520530204241 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93976114658.

The product of its (nonzero) digits is 19200, while the sum is 31.

Adding to 21520530204241 its reverse (14240203502512), we get a palindrome (35760733706753).

The spelling of 21520530204241 in words is "twenty-one trillion, five hundred twenty billion, five hundred thirty million, two hundred four thousand, two hundred forty-one".