213013128521 has 2 divisors, whose sum is σ = 213013128522. Its totient is φ = 213013128520.

The previous prime is 213013128457. The next prime is 213013128593. The reversal of 213013128521 is 125821310312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 146378934025 + 66634194496 = 382595^2 + 258136^2 .

It is a cyclic number.

It is not a de Polignac number, because 213013128521 - 2⁶ = 213013128457 is a prime.

It is not a weakly prime, because it can be changed into another prime (213013128721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106506564260 + 106506564261.

It is an arithmetic number, because the mean of its divisors is an integer number (106506564261).

Almost surely, 2^213013128521 is an apocalyptic number.

It is an amenable number.

213013128521 is a deficient number, since it is larger than the sum of its proper divisors (1).

213013128521 is an equidigital number, since it uses as much as digits as its factorization.

213013128521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2880, while the sum is 29.

Adding to 213013128521 its reverse (125821310312), we get a palindrome (338834438833).

The spelling of 213013128521 in words is "two hundred thirteen billion, thirteen million, one hundred twenty-eight thousand, five hundred twenty-one".