211611561563 has 2 divisors, whose sum is σ = 211611561564. Its totient is φ = 211611561562.

The previous prime is 211611561523. The next prime is 211611561587. The reversal of 211611561563 is 365165116112.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 211611561563 - 2³² = 207316594267 is a prime.

It is not a weakly prime, because it can be changed into another prime (211611561523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105805780781 + 105805780782.

It is an arithmetic number, because the mean of its divisors is an integer number (105805780782).

Almost surely, 2^211611561563 is an apocalyptic number.

211611561563 is a deficient number, since it is larger than the sum of its proper divisors (1).

211611561563 is an equidigital number, since it uses as much as digits as its factorization.

211611561563 is an evil number, because the sum of its binary digits is even.

The product of its digits is 32400, while the sum is 38.

Adding to 211611561563 its reverse (365165116112), we get a palindrome (576776677675).

The spelling of 211611561563 in words is "two hundred eleven billion, six hundred eleven million, five hundred sixty-one thousand, five hundred sixty-three".