211311197857 has 2 divisors, whose sum is σ = 211311197858. Its totient is φ = 211311197856.

The previous prime is 211311197767. The next prime is 211311197869. The reversal of 211311197857 is 758791113112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 144893661201 + 66417536656 = 380649^2 + 257716^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-211311197857 is a prime.

It is not a weakly prime, because it can be changed into another prime (211311197897) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105655598928 + 105655598929.

It is an arithmetic number, because the mean of its divisors is an integer number (105655598929).

Almost surely, 2^211311197857 is an apocalyptic number.

It is an amenable number.

211311197857 is a deficient number, since it is larger than the sum of its proper divisors (1).

211311197857 is an equidigital number, since it uses as much as digits as its factorization.

211311197857 is an evil number, because the sum of its binary digits is even.

The product of its digits is 105840, while the sum is 46.

The spelling of 211311197857 in words is "two hundred eleven billion, three hundred eleven million, one hundred ninety-seven thousand, eight hundred fifty-seven".