640885211 has 2 divisors, whose sum is σ = 640885212. Its totient is φ = 640885210.

The previous prime is 640885183. The next prime is 640885213. The reversal of 640885211 is 112588046.

640885211 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-640885211 is a prime.

Together with 640885213, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (640885213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320442605 + 320442606.

It is an arithmetic number, because the mean of its divisors is an integer number (320442606).

Almost surely, 2^640885211 is an apocalyptic number.

640885211 is a deficient number, since it is larger than the sum of its proper divisors (1).

640885211 is an equidigital number, since it uses as much as digits as its factorization.

640885211 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15360, while the sum is 35.

The square root of 640885211 is about 25315.7107543912. The cubic root of 640885211 is about 862.1710115720.

It can be divided in two parts, 6408 and 85211, that added together give a palindrome (91619).

The spelling of 640885211 in words is "six hundred forty million, eight hundred eighty-five thousand, two hundred eleven".