201122166691 has 2 divisors, whose sum is σ = 201122166692. Its totient is φ = 201122166690.

The previous prime is 201122166677. The next prime is 201122166767. The reversal of 201122166691 is 196661221102.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 201122166691 - 2¹⁵ = 201122133923 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 201122166691.

It is not a weakly prime, because it can be changed into another prime (201122146691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100561083345 + 100561083346.

It is an arithmetic number, because the mean of its divisors is an integer number (100561083346).

Almost surely, 2^201122166691 is an apocalyptic number.

201122166691 is a deficient number, since it is larger than the sum of its proper divisors (1).

201122166691 is an equidigital number, since it uses as much as digits as its factorization.

201122166691 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15552, while the sum is 37.

Adding to 201122166691 its reverse (196661221102), we get a palindrome (397783387793).

The spelling of 201122166691 in words is "two hundred one billion, one hundred twenty-two million, one hundred sixty-six thousand, six hundred ninety-one".