640219367 has 2 divisors, whose sum is σ = 640219368. Its totient is φ = 640219366.

The previous prime is 640219253. The next prime is 640219369. The reversal of 640219367 is 763912046.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 640219367 - 2¹⁸ = 639957223 is a prime.

Together with 640219369, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 640219367.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (640219369) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320109683 + 320109684.

It is an arithmetic number, because the mean of its divisors is an integer number (320109684).

Almost surely, 2^640219367 is an apocalyptic number.

640219367 is a deficient number, since it is larger than the sum of its proper divisors (1).

640219367 is an equidigital number, since it uses as much as digits as its factorization.

640219367 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 54432, while the sum is 38.

The square root of 640219367 is about 25302.5565309120. The cubic root of 640219367 is about 861.8723255726.

The spelling of 640219367 in words is "six hundred forty million, two hundred nineteen thousand, three hundred sixty-seven".