636736 has 14 divisors (see below), whose sum is σ = 1263650. Its totient is φ = 318336.

The previous prime is 636731. The next prime is 636739. The reversal of 636736 is 637636.

It can be written as a sum of positive squares in only one way, i.e., 518400 + 118336 = 720^2 + 344^2 .

It is a junction number, because it is equal to n+sod(n) for n = 636698 and 636707.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (636731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4911 + ... + 5038.

2⁶³⁶⁷³⁶ is an apocalyptic number.

It is an amenable number.

636736 is a deficient number, since it is larger than the sum of its proper divisors (626914).

636736 is an equidigital number, since it uses as much as digits as its factorization.

636736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9961 (or 9951 counting only the distinct ones).

The product of its digits is 13608, while the sum is 31.

The square root of 636736 is about 797.9573923462. The cubic root of 636736 is about 86.0306362816.

Subtracting 636736 from its reverse (637636), we obtain a square (900 = 30²).

The spelling of 636736 in words is "six hundred thirty-six thousand, seven hundred thirty-six".