640437619 has 2 divisors, whose sum is σ = 640437620. Its totient is φ = 640437618.

The previous prime is 640437607. The next prime is 640437631. The reversal of 640437619 is 916734046.

640437619 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a balanced prime because it is at equal distance from previous prime (640437607) and next prime (640437631).

It is a cyclic number.

It is not a de Polignac number, because 640437619 - 2¹¹ = 640435571 is a prime.

It is a super-2 number, since 2×640437619² = 820320687660778322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (640437419) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320218809 + 320218810.

It is an arithmetic number, because the mean of its divisors is an integer number (320218810).

Almost surely, 2^640437619 is an apocalyptic number.

640437619 is a deficient number, since it is larger than the sum of its proper divisors (1).

640437619 is an equidigital number, since it uses as much as digits as its factorization.

640437619 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 108864, while the sum is 40.

The square root of 640437619 is about 25306.8690082357. The cubic root of 640437619 is about 861.9702524174.

The spelling of 640437619 in words is "six hundred forty million, four hundred thirty-seven thousand, six hundred nineteen".