640106237 has 2 divisors, whose sum is σ = 640106238. Its totient is φ = 640106236.

The previous prime is 640106189. The next prime is 640106279. The reversal of 640106237 is 732601046.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 446645956 + 193460281 = 21134^2 + 13909^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-640106237 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 (640102237) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320053118 + 320053119.

It is an arithmetic number, because the mean of its divisors is an integer number (320053119).

Almost surely, 2^640106237 is an apocalyptic number.

It is an amenable number.

640106237 is a deficient number, since it is larger than the sum of its proper divisors (1).

640106237 is an equidigital number, since it uses as much as digits as its factorization.

640106237 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6048, while the sum is 29.

The square root of 640106237 is about 25300.3208872931. The cubic root of 640106237 is about 861.8215568492.

The spelling of 640106237 in words is "six hundred forty million, one hundred six thousand, two hundred thirty-seven".