661101169 has 2 divisors, whose sum is σ = 661101170. Its totient is φ = 661101168.

The previous prime is 661101149. The next prime is 661101187. The reversal of 661101169 is 961101166.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 656640625 + 4460544 = 25625^2 + 2112^2 .

It is a cyclic number.

It is not a de Polignac number, because 661101169 - 2⁵ = 661101137 is a prime.

It is a super-2 number, since 2×661101169² = 874109511306333122, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 661101169.

It is not a weakly prime, because it can be changed into another prime (661101149) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330550584 + 330550585.

It is an arithmetic number, because the mean of its divisors is an integer number (330550585).

Almost surely, 2^661101169 is an apocalyptic number.

It is an amenable number.

661101169 is a deficient number, since it is larger than the sum of its proper divisors (1).

661101169 is an equidigital number, since it uses as much as digits as its factorization.

661101169 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1944, while the sum is 31.

The square root of 661101169 is about 25711.8876981057. The cubic root of 661101169 is about 871.1427134300.

The spelling of 661101169 in words is "six hundred sixty-one million, one hundred one thousand, one hundred sixty-nine".