21533500201313 has 2 divisors, whose sum is σ = 21533500201314. Its totient is φ = 21533500201312.

The previous prime is 21533500201277. The next prime is 21533500201379. The reversal of 21533500201313 is 31310200533512.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20041308469504 + 1492191731809 = 4476752^2 + 1221553^2 .

It is a cyclic number.

It is not a de Polignac number, because 21533500201313 - 2³⁶ = 21464780724577 is a prime.

It is not a weakly prime, because it can be changed into another prime (21533500201813) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10766750100656 + 10766750100657.

It is an arithmetic number, because the mean of its divisors is an integer number (10766750100657).

Almost surely, 2^{21533500201313} is an apocalyptic number.

It is an amenable number.

21533500201313 is a deficient number, since it is larger than the sum of its proper divisors (1).

21533500201313 is an equidigital number, since it uses as much as digits as its factorization.

21533500201313 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8100, while the sum is 29.

Adding to 21533500201313 its reverse (31310200533512), we get a palindrome (52843700734825).

The spelling of 21533500201313 in words is "twenty-one trillion, five hundred thirty-three billion, five hundred million, two hundred one thousand, three hundred thirteen".