6406254661 has 2 divisors, whose sum is σ = 6406254662. Its totient is φ = 6406254660.

The previous prime is 6406254593. The next prime is 6406254667. The reversal of 6406254661 is 1664526046.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5929924036 + 476330625 = 77006^2 + 21825^2 .

It is a cyclic number.

It is not a de Polignac number, because 6406254661 - 2¹⁵ = 6406221893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6406254667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3203127330 + 3203127331.

It is an arithmetic number, because the mean of its divisors is an integer number (3203127331).

Almost surely, 2^6406254661 is an apocalyptic number.

It is an amenable number.

6406254661 is a deficient number, since it is larger than the sum of its proper divisors (1).

6406254661 is an equidigital number, since it uses as much as digits as its factorization.

6406254661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 207360, while the sum is 40.

The square root of 6406254661 is about 80039.0820849415. The cubic root of 6406254661 is about 1857.2401607860.

The spelling of 6406254661 in words is "six billion, four hundred six million, two hundred fifty-four thousand, six hundred sixty-one".