641411809 has 2 divisors, whose sum is σ = 641411810. Its totient is φ = 641411808.

The previous prime is 641411801. The next prime is 641411851. The reversal of 641411809 is 908114146.

641411809 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 504451600 + 136960209 = 22460^2 + 11703^2 .

It is a cyclic number.

It is not a de Polignac number, because 641411809 - 2³ = 641411801 is a prime.

It is a super-2 number, since 2×641411809² = 822818217449304962, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (641411801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320705904 + 320705905.

It is an arithmetic number, because the mean of its divisors is an integer number (320705905).

Almost surely, 2^641411809 is an apocalyptic number.

It is an amenable number.

641411809 is a deficient number, since it is larger than the sum of its proper divisors (1).

641411809 is an equidigital number, since it uses as much as digits as its factorization.

641411809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6912, while the sum is 34.

The square root of 641411809 is about 25326.1092353326. The cubic root of 641411809 is about 862.4070877720.

The spelling of 641411809 in words is "six hundred forty-one million, four hundred eleven thousand, eight hundred nine".