640140601 has 3 divisors (see below), whose sum is σ = 640165903. Its totient is φ = 640115300.

The previous prime is 640140547. The next prime is 640140617. The reversal of 640140601 is 106041046.

The square root of 640140601 is 25301.

It is a perfect power (a square), and thus also a powerful number.

640140601 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 106041046 = 2 ⋅53020523.

It can be written as a sum of positive squares in only one way, i.e., 412130601 + 228010000 = 20301^2 + 15100^2 .

It is not a de Polignac number, because 640140601 - 2¹⁵ = 640107833 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (640140671) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 12651 + ... + 37951.

Almost surely, 2^640140601 is an apocalyptic number.

640140601 is the 25301-st square number.

640140601 is the 12651-st centered octagonal number.

It is an amenable number.

640140601 is a deficient number, since it is larger than the sum of its proper divisors (25302).

640140601 is an frugal number, since it uses more digits than its factorization.

640140601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50602 (or 25301 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 22.

The cubic root of 640140601 is about 861.8369788236.

Multiplying 640140601 by its product of nonzero digits (576), we get a square (368720986176 = 607224²).

Adding to 640140601 its reverse (106041046), we get a palindrome (746181647).

The spelling of 640140601 in words is "six hundred forty million, one hundred forty thousand, six hundred one".