5201401661 has 2 divisors, whose sum is σ = 5201401662. Its totient is φ = 5201401660.

The previous prime is 5201401649. The next prime is 5201401721. The reversal of 5201401661 is 1661041025.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5137305625 + 64096036 = 71675^2 + 8006^2 .

It is a cyclic number.

It is not a de Polignac number, because 5201401661 - 2¹⁰ = 5201400637 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 5201401661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (5201400661) 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, 2600700830 + 2600700831.

It is an arithmetic number, because the mean of its divisors is an integer number (2600700831).

Almost surely, 2^5201401661 is an apocalyptic number.

It is an amenable number.

5201401661 is a deficient number, since it is larger than the sum of its proper divisors (1).

5201401661 is an equidigital number, since it uses as much as digits as its factorization.

5201401661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 5201401661 is about 72120.7436248407. The cubic root of 5201401661 is about 1732.6338599758.

Adding to 5201401661 its reverse (1661041025), we get a palindrome (6862442686).

The spelling of 5201401661 in words is "five billion, two hundred one million, four hundred one thousand, six hundred sixty-one".