640065499 has 2 divisors, whose sum is σ = 640065500. Its totient is φ = 640065498.

The previous prime is 640065457. The next prime is 640065509. The reversal of 640065499 is 994560046.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 640065499 - 2⁹ = 640064987 is a prime.

It is a super-3 number, since 3×640065499³ (a number of 27 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (640065299) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320032749 + 320032750.

It is an arithmetic number, because the mean of its divisors is an integer number (320032750).

Almost surely, 2^640065499 is an apocalyptic number.

640065499 is a deficient number, since it is larger than the sum of its proper divisors (1).

640065499 is an equidigital number, since it uses as much as digits as its factorization.

640065499 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 233280, while the sum is 43.

The square root of 640065499 is about 25299.5157858802. The cubic root of 640065499 is about 861.8032736178.

The spelling of 640065499 in words is "six hundred forty million, sixty-five thousand, four hundred ninety-nine".