211230025752661 has 2 divisors, whose sum is σ = 211230025752662. Its totient is φ = 211230025752660.

The previous prime is 211230025752617. The next prime is 211230025752677. The reversal of 211230025752661 is 166257520032112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 127315815131761 + 83914210620900 = 11283431^2 + 9160470^2 .

It is a cyclic number.

It is not a de Polignac number, because 211230025752661 - 2²³ = 211230017364053 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (211230025750661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105615012876330 + 105615012876331.

It is an arithmetic number, because the mean of its divisors is an integer number (105615012876331).

Almost surely, 2^{211230025752661} is an apocalyptic number.

It is an amenable number.

211230025752661 is a deficient number, since it is larger than the sum of its proper divisors (1).

211230025752661 is an equidigital number, since it uses as much as digits as its factorization.

211230025752661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 302400, while the sum is 43.

Adding to 211230025752661 its reverse (166257520032112), we get a palindrome (377487545784773).

The spelling of 211230025752661 in words is "two hundred eleven trillion, two hundred thirty billion, twenty-five million, seven hundred fifty-two thousand, six hundred sixty-one".