211021211977 has 2 divisors, whose sum is σ = 211021211978. Its totient is φ = 211021211976.

The previous prime is 211021211971. The next prime is 211021211981. The reversal of 211021211977 is 779112120112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 206598429961 + 4422782016 = 454531^2 + 66504^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-211021211977 is a prime.

It is not a weakly prime, because it can be changed into another prime (211021211971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105510605988 + 105510605989.

It is an arithmetic number, because the mean of its divisors is an integer number (105510605989).

Almost surely, 2^211021211977 is an apocalyptic number.

It is an amenable number.

211021211977 is a deficient number, since it is larger than the sum of its proper divisors (1).

211021211977 is an equidigital number, since it uses as much as digits as its factorization.

211021211977 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3528, while the sum is 34.

The spelling of 211021211977 in words is "two hundred eleven billion, twenty-one million, two hundred eleven thousand, nine hundred seventy-seven".