641804879 has 2 divisors, whose sum is σ = 641804880. Its totient is φ = 641804878.

The previous prime is 641804861. The next prime is 641804897. The reversal of 641804879 is 978408146.

Together with next prime (641804897) it forms an Ormiston pair, because they use the same digits, order apart.

It is a balanced prime because it is at equal distance from previous prime (641804861) and next prime (641804897).

It is a cyclic number.

It is not a de Polignac number, because 641804879 - 2⁸ = 641804623 is a prime.

It is a pancake number, because a pancake can be divided into 641804879 parts by 35827 straight cuts.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (641804809) 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, 320902439 + 320902440.

It is an arithmetic number, because the mean of its divisors is an integer number (320902440).

Almost surely, 2^641804879 is an apocalyptic number.

641804879 is a deficient number, since it is larger than the sum of its proper divisors (1).

641804879 is an equidigital number, since it uses as much as digits as its factorization.

641804879 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 387072, while the sum is 47.

The square root of 641804879 is about 25333.8682202304. The cubic root of 641804879 is about 862.5832185754.

The spelling of 641804879 in words is "six hundred forty-one million, eight hundred four thousand, eight hundred seventy-nine".