640837209611 has 2 divisors, whose sum is σ = 640837209612. Its totient is φ = 640837209610.

The previous prime is 640837209559. The next prime is 640837209613. The reversal of 640837209611 is 116902738046.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 640837209611 - 2³⁰ = 639763467787 is a prime.

Together with 640837209613, 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 (640837209613) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320418604805 + 320418604806.

It is an arithmetic number, because the mean of its divisors is an integer number (320418604806).

Almost surely, 2^640837209611 is an apocalyptic number.

640837209611 is a deficient number, since it is larger than the sum of its proper divisors (1).

640837209611 is an equidigital number, since it uses as much as digits as its factorization.

640837209611 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 435456, while the sum is 47.

The spelling of 640837209611 in words is "six hundred forty billion, eight hundred thirty-seven million, two hundred nine thousand, six hundred eleven".