636340 has 12 divisors (see below), whose sum is σ = 1336356. Its totient is φ = 254528.

The previous prime is 636331. The next prime is 636343. The reversal of 636340 is 43636.

636340 = T₁₅₈ + T₁₅₉ + ... + T₁₉₇.

It can be written as a sum of positive squares in 2 ways, for example, as 417316 + 219024 = 646^2 + 468^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (636343) by changing a digit.

636340 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15889 + ... + 15928.

It is an arithmetic number, because the mean of its divisors is an integer number (111363).

2⁶³⁶³⁴⁰ is an apocalyptic number.

It is an amenable number.

636340 is an abundant number, since it is smaller than the sum of its proper divisors (700016).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

636340 is a wasteful number, since it uses less digits than its factorization.

636340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31826 (or 31824 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 22.

The square root of 636340 is about 797.7092202050. The cubic root of 636340 is about 86.0127978070.

Adding to 636340 its reverse (43636), we get a palindrome (679976).

Subtracting from 636340 its reverse (43636), we obtain a cube (592704 = 84³).

The spelling of 636340 in words is "six hundred thirty-six thousand, three hundred forty".