221145404 has 12 divisors (see below), whose sum is σ = 392455728. Its totient is φ = 109015200.

The previous prime is 221145377. The next prime is 221145439. The reversal of 221145404 is 404541122.

It is a self number, because there is not a number n which added to its sum of digits gives 221145404.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 389057 + ... + 389624.

It is an arithmetic number, because the mean of its divisors is an integer number (32704644).

Almost surely, 2^221145404 is an apocalyptic number.

It is an amenable number.

221145404 is a deficient number, since it is larger than the sum of its proper divisors (171310324).

221145404 is a wasteful number, since it uses less digits than its factorization.

221145404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 778756 (or 778754 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 23.

The square root of 221145404 is about 14870.9584089258. The cubic root of 221145404 is about 604.7269254617.

Adding to 221145404 its reverse (404541122), we get a palindrome (625686526).

The spelling of 221145404 in words is "two hundred twenty-one million, one hundred forty-five thousand, four hundred four".