640076243 has 4 divisors (see below), whose sum is σ = 640127520. Its totient is φ = 640024968.

The previous prime is 640076219. The next prime is 640076257. The reversal of 640076243 is 342670046.

640076243 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.

It is a cyclic number.

It is not a de Polignac number, because 640076243 - 2⁶ = 640076179 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (640073243) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6593 + ... + 36381.

It is an arithmetic number, because the mean of its divisors is an integer number (160031880).

Almost surely, 2^640076243 is an apocalyptic number.

640076243 is a deficient number, since it is larger than the sum of its proper divisors (51277).

640076243 is a wasteful number, since it uses less digits than its factorization.

640076243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51276.

The product of its (nonzero) digits is 24192, while the sum is 32.

The square root of 640076243 is about 25299.7281210688. The cubic root of 640076243 is about 861.8080956048.

The spelling of 640076243 in words is "six hundred forty million, seventy-six thousand, two hundred forty-three".