636734401 has 4 divisors (see below), whose sum is σ = 643038804. Its totient is φ = 630430000.

The previous prime is 636734393. The next prime is 636734407. The reversal of 636734401 is 104437636.

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

It can be written as a sum of positive squares in 2 ways, for example, as 588014001 + 48720400 = 24249^2 + 6980^2 .

It is a cyclic number.

It is not a de Polignac number, because 636734401 - 2³ = 636734393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (636734407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3152050 + ... + 3152251.

It is an arithmetic number, because the mean of its divisors is an integer number (160759701).

Almost surely, 2^636734401 is an apocalyptic number.

It is an amenable number.

636734401 is a deficient number, since it is larger than the sum of its proper divisors (6304403).

636734401 is a wasteful number, since it uses less digits than its factorization.

636734401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6304402.

The product of its (nonzero) digits is 36288, while the sum is 34.

The square root of 636734401 is about 25233.5966718976. The cubic root of 636734401 is about 860.3056426692.

The spelling of 636734401 in words is "six hundred thirty-six million, seven hundred thirty-four thousand, four hundred one".