6431641 has 2 divisors, whose sum is σ = 6431642. Its totient is φ = 6431640.

The previous prime is 6431597. The next prime is 6431653. The reversal of 6431641 is 1461346.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5621641 + 810000 = 2371^2 + 900^2 .

It is a cyclic number.

It is not a de Polignac number, because 6431641 - 2¹³ = 6423449 is a prime.

6431641 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (6431681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3215820 + 3215821.

It is an arithmetic number, because the mean of its divisors is an integer number (3215821).

Almost surely, 2^6431641 is an apocalyptic number.

It is an amenable number.

6431641 is a deficient number, since it is larger than the sum of its proper divisors (1).

6431641 is an equidigital number, since it uses as much as digits as its factorization.

6431641 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1728, while the sum is 25.

The square root of 6431641 is about 2536.0680195925. The cubic root of 6431641 is about 185.9690182335.

Adding to 6431641 its reverse (1461346), we get a palindrome (7892987).

It can be divided in two parts, 64316 and 41, that multiplied together give a triangular number (2636956 = T₂₂₉₆).

The spelling of 6431641 in words is "six million, four hundred thirty-one thousand, six hundred forty-one".