640871735916619 has 2 divisors, whose sum is σ = 640871735916620. Its totient is φ = 640871735916618.

The previous prime is 640871735916571. The next prime is 640871735916767. The reversal of 640871735916619 is 916619537178046.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 640871735916619 - 2¹⁹ = 640871735392331 is a prime.

It is a super-2 number, since 2×640871735916619² (a number of 30 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (640871739916619) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320435867958309 + 320435867958310.

It is an arithmetic number, because the mean of its divisors is an integer number (320435867958310).

Almost surely, 2^{640871735916619} is an apocalyptic number.

640871735916619 is a deficient number, since it is larger than the sum of its proper divisors (1).

640871735916619 is an equidigital number, since it uses as much as digits as its factorization.

640871735916619 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 411505920, while the sum is 73.

The spelling of 640871735916619 in words is "six hundred forty trillion, eight hundred seventy-one billion, seven hundred thirty-five million, nine hundred sixteen thousand, six hundred nineteen".