640277492 has 12 divisors (see below), whose sum is σ = 1122458820. Its totient is φ = 319574976.

The previous prime is 640277483. The next prime is 640277497. The reversal of 640277492 is 294772046.

It can be written as a sum of positive squares in 2 ways, for example, as 259403236 + 380874256 = 16106^2 + 19516^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640277497) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 138383 + ... + 142934.

It is an arithmetic number, because the mean of its divisors is an integer number (93538235).

Almost surely, 2^640277492 is an apocalyptic number.

It is an amenable number.

640277492 is a deficient number, since it is larger than the sum of its proper divisors (482181328).

640277492 is a wasteful number, since it uses less digits than its factorization.

640277492 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 281890 (or 281888 counting only the distinct ones).

The product of its (nonzero) digits is 169344, while the sum is 41.

The square root of 640277492 is about 25303.7051041937. The cubic root of 640277492 is about 861.8984076811.

The spelling of 640277492 in words is "six hundred forty million, two hundred seventy-seven thousand, four hundred ninety-two".