6461405989 has 2 divisors, whose sum is σ = 6461405990. Its totient is φ = 6461405988.

The previous prime is 6461405959. The next prime is 6461406047. The reversal of 6461405989 is 9895041646.

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., 3264408225 + 3196997764 = 57135^2 + 56542^2 .

It is a cyclic number.

It is not a de Polignac number, because 6461405989 - 2⁵ = 6461405957 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6461405959) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3230702994 + 3230702995.

It is an arithmetic number, because the mean of its divisors is an integer number (3230702995).

Almost surely, 2^6461405989 is an apocalyptic number.

It is an amenable number.

6461405989 is a deficient number, since it is larger than the sum of its proper divisors (1).

6461405989 is an equidigital number, since it uses as much as digits as its factorization.

6461405989 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1866240, while the sum is 52.

The square root of 6461405989 is about 80382.8712413285. The cubic root of 6461405989 is about 1862.5545879771.

The spelling of 6461405989 in words is "six billion, four hundred sixty-one million, four hundred five thousand, nine hundred eighty-nine".