6720637213 has 2 divisors, whose sum is σ = 6720637214. Its totient is φ = 6720637212.

The previous prime is 6720637211. The next prime is 6720637223. The reversal of 6720637213 is 3127360276.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3687161284 + 3033475929 = 60722^2 + 55077^2 .

It is a cyclic number.

It is not a de Polignac number, because 6720637213 - 2¹ = 6720637211 is a prime.

Together with 6720637211, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6720637211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3360318606 + 3360318607.

It is an arithmetic number, because the mean of its divisors is an integer number (3360318607).

Almost surely, 2^6720637213 is an apocalyptic number.

It is an amenable number.

6720637213 is a deficient number, since it is larger than the sum of its proper divisors (1).

6720637213 is an equidigital number, since it uses as much as digits as its factorization.

6720637213 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 63504, while the sum is 37.

The square root of 6720637213 is about 81979.4926368784. The cubic root of 6720637213 is about 1887.1372365893.

Adding to 6720637213 its reverse (3127360276), we get a palindrome (9847997489).

The spelling of 6720637213 in words is "six billion, seven hundred twenty million, six hundred thirty-seven thousand, two hundred thirteen".