634666221 has 24 divisors (see below), whose sum is σ = 1048748480. Its totient is φ = 362304576.

The previous prime is 634666211. The next prime is 634666237. The reversal of 634666221 is 122666436.

It is not a de Polignac number, because 634666221 - 2⁶ = 634666157 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (634666211) 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 23 ways as a sum of consecutive naturals, for example, 66666 + ... + 75588.

Almost surely, 2^634666221 is an apocalyptic number.

It is an amenable number.

634666221 is a deficient number, since it is larger than the sum of its proper divisors (414082259).

634666221 is a wasteful number, since it uses less digits than its factorization.

634666221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10065 (or 10062 counting only the distinct ones).

The product of its digits is 62208, while the sum is 36.

The square root of 634666221 is about 25192.5826583937. The cubic root of 634666221 is about 859.3731780916.

The spelling of 634666221 in words is "six hundred thirty-four million, six hundred sixty-six thousand, two hundred twenty-one".