3126405661 has 2 divisors, whose sum is σ = 3126405662. Its totient is φ = 3126405660.

The previous prime is 3126405641. The next prime is 3126405679. The reversal of 3126405661 is 1665046213.

3126405661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2830772025 + 295633636 = 53205^2 + 17194^2 .

It is a cyclic number.

It is not a de Polignac number, because 3126405661 - 2⁵ = 3126405629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3126405631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1563202830 + 1563202831.

It is an arithmetic number, because the mean of its divisors is an integer number (1563202831).

Almost surely, 2^3126405661 is an apocalyptic number.

It is an amenable number.

3126405661 is a deficient number, since it is larger than the sum of its proper divisors (1).

3126405661 is an equidigital number, since it uses as much as digits as its factorization.

3126405661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25920, while the sum is 34.

The square root of 3126405661 is about 55914.2706381832. The cubic root of 3126405661 is about 1462.2280457242.

The spelling of 3126405661 in words is "three billion, one hundred twenty-six million, four hundred five thousand, six hundred sixty-one".