640212227 has 2 divisors, whose sum is σ = 640212228. Its totient is φ = 640212226.

The previous prime is 640212203. The next prime is 640212233. The reversal of 640212227 is 722212046.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 640212227 - 2¹⁶ = 640146691 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 640212196 and 640212205.

It is not a weakly prime, because it can be changed into another prime (640212247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320106113 + 320106114.

It is an arithmetic number, because the mean of its divisors is an integer number (320106114).

Almost surely, 2^640212227 is an apocalyptic number.

640212227 is a deficient number, since it is larger than the sum of its proper divisors (1).

640212227 is an equidigital number, since it uses as much as digits as its factorization.

640212227 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2688, while the sum is 26.

The square root of 640212227 is about 25302.4154380565. The cubic root of 640212227 is about 861.8691215712.

The spelling of 640212227 in words is "six hundred forty million, two hundred twelve thousand, two hundred twenty-seven".