636743 has 4 divisors (see below), whose sum is σ = 638400. Its totient is φ = 635088.

The previous prime is 636739. The next prime is 636749. The reversal of 636743 is 347636.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 636743 - 2² = 636739 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (636749) 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, 83 + ... + 1131.

It is an arithmetic number, because the mean of its divisors is an integer number (159600).

2⁶³⁶⁷⁴³ is an apocalyptic number.

636743 is a deficient number, since it is larger than the sum of its proper divisors (1657).

636743 is a wasteful number, since it uses less digits than its factorization.

636743 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1656.

The product of its digits is 9072, while the sum is 29.

The square root of 636743 is about 797.9617785333. The cubic root of 636743 is about 86.0309515417.

The spelling of 636743 in words is "six hundred thirty-six thousand, seven hundred forty-three".