13771661 has 2 divisors, whose sum is σ = 13771662. Its totient is φ = 13771660.

The previous prime is 13771643. The next prime is 13771663. The reversal of 13771661 is 16617731.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13645636 + 126025 = 3694^2 + 355^2 .

It is a cyclic number.

It is not a de Polignac number, because 13771661 - 2¹⁰ = 13770637 is a prime.

It is a super-3 number, since 3×13771661³ (a number of 22 digits) contains 333 as substring.

It is a Sophie Germain prime.

Together with 13771663, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13771663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6885830 + 6885831.

It is an arithmetic number, because the mean of its divisors is an integer number (6885831).

Almost surely, 2^13771661 is an apocalyptic number.

It is an amenable number.

13771661 is a deficient number, since it is larger than the sum of its proper divisors (1).

13771661 is an equidigital number, since it uses as much as digits as its factorization.

13771661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5292, while the sum is 32.

The square root of 13771661 is about 3711.0188627923. The cubic root of 13771661 is about 239.6967292084.

The spelling of 13771661 in words is "thirteen million, seven hundred seventy-one thousand, six hundred sixty-one".