5011661 has 2 divisors, whose sum is σ = 5011662. Its totient is φ = 5011660.

The previous prime is 5011639. The next prime is 5011729. The reversal of 5011661 is 1661105.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 4813636 + 198025 = 2194^2 + 445^2 .

It is a cyclic number.

It is not a de Polignac number, because 5011661 - 2¹⁰ = 5010637 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (5011621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2505830 + 2505831.

It is an arithmetic number, because the mean of its divisors is an integer number (2505831).

Almost surely, 2^5011661 is an apocalyptic number.

It is an amenable number.

5011661 is a deficient number, since it is larger than the sum of its proper divisors (1).

5011661 is an equidigital number, since it uses as much as digits as its factorization.

5011661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 180, while the sum is 20.

The square root of 5011661 is about 2238.6739378480. The cubic root of 5011661 is about 171.1304249889.

Adding to 5011661 its reverse (1661105), we get a palindrome (6672766).

It can be divided in two parts, 50 and 11661, that added together give a palindrome (11711).

The spelling of 5011661 in words is "five million, eleven thousand, six hundred sixty-one".