640367 has 16 divisors (see below), whose sum is σ = 817152. Its totient is φ = 488160.

The previous prime is 640363. The next prime is 640369. The reversal of 640367 is 763046.

It is a cyclic number.

It is not a de Polignac number, because 640367 - 2² = 640363 is a prime.

It is a Smith number, since the sum of its digits (26) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 640367.

It is not an unprimeable number, because it can be changed into a prime (640363) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2708 + ... + 2934.

It is an arithmetic number, because the mean of its divisors is an integer number (51072).

2⁶⁴⁰³⁶⁷ is an apocalyptic number.

640367 is a deficient number, since it is larger than the sum of its proper divisors (176785).

640367 is a wasteful number, since it uses less digits than its factorization.

640367 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 278.

The product of its (nonzero) digits is 3024, while the sum is 26.

The square root of 640367 is about 800.2293421264. The cubic root of 640367 is about 86.1938569022.

The spelling of 640367 in words is "six hundred forty thousand, three hundred sixty-seven".