635966 has 4 divisors (see below), whose sum is σ = 953952. Its totient is φ = 317982.

The previous prime is 635959. The next prime is 635969. The reversal of 635966 is 669536.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (635969) by changing a digit.

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 as a sum of consecutive naturals, namely, 158990 + ... + 158993.

It is an arithmetic number, because the mean of its divisors is an integer number (238488).

2⁶³⁵⁹⁶⁶ is an apocalyptic number.

635966 is a deficient number, since it is larger than the sum of its proper divisors (317986).

635966 is a wasteful number, since it uses less digits than its factorization.

635966 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 317985.

The product of its digits is 29160, while the sum is 35.

The square root of 635966 is about 797.4747644910. The cubic root of 635966 is about 85.9959435620.

The spelling of 635966 in words is "six hundred thirty-five thousand, nine hundred sixty-six".