21225005213 has 2 divisors, whose sum is σ = 21225005214. Its totient is φ = 21225005212.

The previous prime is 21225005159. The next prime is 21225005293. The reversal of 21225005213 is 31250052212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21204601924 + 20403289 = 145618^2 + 4517^2 .

It is a cyclic number.

It is not a de Polignac number, because 21225005213 - 2⁶ = 21225005149 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21225005293) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10612502606 + 10612502607.

It is an arithmetic number, because the mean of its divisors is an integer number (10612502607).

Almost surely, 2^21225005213 is an apocalyptic number.

It is an amenable number.

21225005213 is a deficient number, since it is larger than the sum of its proper divisors (1).

21225005213 is an equidigital number, since it uses as much as digits as its factorization.

21225005213 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1200, while the sum is 23.

Adding to 21225005213 its reverse (31250052212), we get a palindrome (52475057425).

The spelling of 21225005213 in words is "twenty-one billion, two hundred twenty-five million, five thousand, two hundred thirteen".