20512213 has 2 divisors, whose sum is σ = 20512214. Its totient is φ = 20512212.

The previous prime is 20512201. The next prime is 20512223. The reversal of 20512213 is 31221502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12794929 + 7717284 = 3577^2 + 2778^2 .

It is a cyclic number.

It is not a de Polignac number, because 20512213 - 2⁵ = 20512181 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20512223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10256106 + 10256107.

It is an arithmetic number, because the mean of its divisors is an integer number (10256107).

Almost surely, 2^20512213 is an apocalyptic number.

It is an amenable number.

20512213 is a deficient number, since it is larger than the sum of its proper divisors (1).

20512213 is an equidigital number, since it uses as much as digits as its factorization.

20512213 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 20512213 is about 4529.0410684824. The cubic root of 20512213 is about 273.7395228227.

Adding to 20512213 its reverse (31221502), we get a palindrome (51733715).

The spelling of 20512213 in words is "twenty million, five hundred twelve thousand, two hundred thirteen".