640414987 has 2 divisors, whose sum is σ = 640414988. Its totient is φ = 640414986.

The previous prime is 640414937. The next prime is 640414991. The reversal of 640414987 is 789414046.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 640414987 - 2¹⁵ = 640382219 is a prime.

It is not a weakly prime, because it can be changed into another prime (640414927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320207493 + 320207494.

It is an arithmetic number, because the mean of its divisors is an integer number (320207494).

Almost surely, 2^640414987 is an apocalyptic number.

640414987 is a deficient number, since it is larger than the sum of its proper divisors (1).

640414987 is an equidigital number, since it uses as much as digits as its factorization.

640414987 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 193536, while the sum is 43.

The square root of 640414987 is about 25306.4218529606. The cubic root of 640414987 is about 861.9600987662.

The spelling of 640414987 in words is "six hundred forty million, four hundred fourteen thousand, nine hundred eighty-seven".