641871047 has 2 divisors, whose sum is σ = 641871048. Its totient is φ = 641871046.

The previous prime is 641871011. The next prime is 641871071. The reversal of 641871047 is 740178146.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 641871047 - 2¹⁶ = 641805511 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 641871047.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (641871247) 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, 320935523 + 320935524.

It is an arithmetic number, because the mean of its divisors is an integer number (320935524).

Almost surely, 2^641871047 is an apocalyptic number.

641871047 is a deficient number, since it is larger than the sum of its proper divisors (1).

641871047 is an equidigital number, since it uses as much as digits as its factorization.

641871047 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 37632, while the sum is 38.

The square root of 641871047 is about 25335.1741063684. The cubic root of 641871047 is about 862.6128607335.

The spelling of 641871047 in words is "six hundred forty-one million, eight hundred seventy-one thousand, forty-seven".