640371227 has 2 divisors, whose sum is σ = 640371228. Its totient is φ = 640371226.

The previous prime is 640371161. The next prime is 640371271. The reversal of 640371227 is 722173046.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 640371227 - 2¹⁶ = 640305691 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 640371193 and 640371202.

It is not a weakly prime, because it can be changed into another prime (640374227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320185613 + 320185614.

It is an arithmetic number, because the mean of its divisors is an integer number (320185614).

Almost surely, 2^640371227 is an apocalyptic number.

640371227 is a deficient number, since it is larger than the sum of its proper divisors (1).

640371227 is an equidigital number, since it uses as much as digits as its factorization.

640371227 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 14112, while the sum is 32.

The square root of 640371227 is about 25305.5572355165. The cubic root of 640371227 is about 861.9404655420.

The spelling of 640371227 in words is "six hundred forty million, three hundred seventy-one thousand, two hundred twenty-seven".