640270772 has 12 divisors (see below), whose sum is σ = 1122294180. Its totient is φ = 319615296.

The previous prime is 640270739. The next prime is 640270777. The reversal of 640270772 is 277072046.

It can be written as a sum of positive squares in 2 ways, for example, as 57820816 + 582449956 = 7604^2 + 24134^2 .

It is a super-2 number, since 2×640270772² = 819893322954951968, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640270777) 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 3 ways as a sum of consecutive naturals, for example, 127247 + ... + 132182.

It is an arithmetic number, because the mean of its divisors is an integer number (93524515).

Almost surely, 2^640270772 is an apocalyptic number.

It is an amenable number.

640270772 is a deficient number, since it is larger than the sum of its proper divisors (482023408).

640270772 is a wasteful number, since it uses less digits than its factorization.

640270772 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 260050 (or 260048 counting only the distinct ones).

The product of its (nonzero) digits is 32928, while the sum is 35.

The square root of 640270772 is about 25303.5723169674. The cubic root of 640270772 is about 861.8953923335.

The spelling of 640270772 in words is "six hundred forty million, two hundred seventy thousand, seven hundred seventy-two".