636805225 has 45 divisors (see below), whose sum is σ = 930220503. Its totient is φ = 432426960.

The previous prime is 636805219. The next prime is 636805249. The reversal of 636805225 is 522508636.

It is a happy number.

The square root of 636805225 is 25235.

It is a perfect power (a square), and thus also a powerful number.

636805225 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 229249881 + 407555344 = 15141^2 + 20188^2 .

It is not a de Polignac number, because 636805225 - 2³ = 636805217 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 6182524 + ... + 6182626.

Almost surely, 2^636805225 is an apocalyptic number.

636805225 is the 25235-th square number.

636805225 is the 12618-th centered octagonal number.

It is an amenable number.

636805225 is a deficient number, since it is larger than the sum of its proper divisors (293415278).

636805225 is an frugal number, since it uses more digits than its factorization.

636805225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 244 (or 115 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 37.

The cubic root of 636805225 is about 860.3375387669.

The spelling of 636805225 in words is "six hundred thirty-six million, eight hundred five thousand, two hundred twenty-five".