634221403 has 4 divisors (see below), whose sum is σ = 651362560. Its totient is φ = 617080248.

The previous prime is 634221391. The next prime is 634221449. The reversal of 634221403 is 304122436.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-634221403 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (634221493) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8570523 + ... + 8570596.

It is an arithmetic number, because the mean of its divisors is an integer number (162840640).

Almost surely, 2^634221403 is an apocalyptic number.

634221403 is a deficient number, since it is larger than the sum of its proper divisors (17141157).

634221403 is a wasteful number, since it uses less digits than its factorization.

634221403 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17141156.

The product of its (nonzero) digits is 3456, while the sum is 25.

The square root of 634221403 is about 25183.7527584751. The cubic root of 634221403 is about 859.1723617746.

Adding to 634221403 its reverse (304122436), we get a palindrome (938343839).

The spelling of 634221403 in words is "six hundred thirty-four million, two hundred twenty-one thousand, four hundred three".