640546199 has 2 divisors, whose sum is σ = 640546200. Its totient is φ = 640546198.

The previous prime is 640546187. The next prime is 640546219. The reversal of 640546199 is 991645046.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-640546199 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (640546129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320273099 + 320273100.

It is an arithmetic number, because the mean of its divisors is an integer number (320273100).

Almost surely, 2^640546199 is an apocalyptic number.

640546199 is a deficient number, since it is larger than the sum of its proper divisors (1).

640546199 is an equidigital number, since it uses as much as digits as its factorization.

640546199 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 44.

The square root of 640546199 is about 25309.0141846734. The cubic root of 640546199 is about 862.0189625693.

The spelling of 640546199 in words is "six hundred forty million, five hundred forty-six thousand, one hundred ninety-nine".