211020030721 has 2 divisors, whose sum is σ = 211020030722. Its totient is φ = 211020030720.

The previous prime is 211020030671. The next prime is 211020030731. The reversal of 211020030721 is 127030020112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 161230356225 + 49789674496 = 401535^2 + 223136^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-211020030721 is a prime.

It is not a weakly prime, because it can be changed into another prime (211020030731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105510015360 + 105510015361.

It is an arithmetic number, because the mean of its divisors is an integer number (105510015361).

Almost surely, 2^211020030721 is an apocalyptic number.

It is an amenable number.

211020030721 is a deficient number, since it is larger than the sum of its proper divisors (1).

211020030721 is an equidigital number, since it uses as much as digits as its factorization.

211020030721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 168, while the sum is 19.

Adding to 211020030721 its reverse (127030020112), we get a palindrome (338050050833).

The spelling of 211020030721 in words is "two hundred eleven billion, twenty million, thirty thousand, seven hundred twenty-one".