661563114211 has 4 divisors (see below), whose sum is σ = 670880904624. Its totient is φ = 652245323800.

The previous prime is 661563114197. The next prime is 661563114239. The reversal of 661563114211 is 112411365166.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 112411365166 = 2 ⋅56205682583.

It is a cyclic number.

It is not a de Polignac number, because 661563114211 - 2⁹ = 661563113699 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (661563111211) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4658895100 + ... + 4658895241.

It is an arithmetic number, because the mean of its divisors is an integer number (167720226156).

Almost surely, 2^661563114211 is an apocalyptic number.

661563114211 is a deficient number, since it is larger than the sum of its proper divisors (9317790413).

661563114211 is an equidigital number, since it uses as much as digits as its factorization.

661563114211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9317790412.

The product of its digits is 25920, while the sum is 37.

Adding to 661563114211 its reverse (112411365166), we get a palindrome (773974479377).

The spelling of 661563114211 in words is "six hundred sixty-one billion, five hundred sixty-three million, one hundred fourteen thousand, two hundred eleven".