640039077 has 60 divisors (see below), whose sum is σ = 1018483620. Its totient is φ = 400038912.

The previous prime is 640039027. The next prime is 640039079. The reversal of 640039077 is 770930046.

640039077 is a `hidden beast` number, since 640 + 0 + 3 + 9 + 0 + 7 + 7 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 29257281 + 610781796 = 5409^2 + 24714^2 .

It is not a de Polignac number, because 640039077 - 2⁸ = 640038821 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640039079) 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 in 59 ways as a sum of consecutive naturals, for example, 6598293 + ... + 6598389.

It is an arithmetic number, because the mean of its divisors is an integer number (16974727).

Almost surely, 2^640039077 is an apocalyptic number.

It is an amenable number.

640039077 is a deficient number, since it is larger than the sum of its proper divisors (378444543).

640039077 is an equidigital number, since it uses as much as digits as its factorization.

640039077 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 244 (or 182 counting only the distinct ones).

The product of its (nonzero) digits is 31752, while the sum is 36.

The square root of 640039077 is about 25298.9935965840. The cubic root of 640039077 is about 861.7914149984.

The spelling of 640039077 in words is "six hundred forty million, thirty-nine thousand, seventy-seven".