641896477 has 2 divisors, whose sum is σ = 641896478. Its totient is φ = 641896476.

The previous prime is 641896379. The next prime is 641896483. The reversal of 641896477 is 774698146.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 445167801 + 196728676 = 21099^2 + 14026^2 .

It is a cyclic number.

It is not a de Polignac number, because 641896477 - 2⁷ = 641896349 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (641896777) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320948238 + 320948239.

It is an arithmetic number, because the mean of its divisors is an integer number (320948239).

Almost surely, 2^641896477 is an apocalyptic number.

It is an amenable number.

641896477 is a deficient number, since it is larger than the sum of its proper divisors (1).

641896477 is an equidigital number, since it uses as much as digits as its factorization.

641896477 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2032128, while the sum is 52.

The square root of 641896477 is about 25335.6759728254. The cubic root of 641896477 is about 862.6242524066.

The spelling of 641896477 in words is "six hundred forty-one million, eight hundred ninety-six thousand, four hundred seventy-seven".