221451404 has 12 divisors (see below), whose sum is σ = 395785824. Its totient is φ = 108369744.

The previous prime is 221451361. The next prime is 221451409. The reversal of 221451404 is 404154122.

It is a self number, because there is not a number n which added to its sum of digits gives 221451404.

It is not an unprimeable number, because it can be changed into a prime (221451409) 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, 588779 + ... + 589154.

It is an arithmetic number, because the mean of its divisors is an integer number (32982152).

Almost surely, 2^221451404 is an apocalyptic number.

It is an amenable number.

221451404 is a deficient number, since it is larger than the sum of its proper divisors (174334420).

221451404 is a wasteful number, since it uses less digits than its factorization.

221451404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1177984 (or 1177982 counting only the distinct ones).

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

The square root of 221451404 is about 14881.2433620313. The cubic root of 221451404 is about 605.0057181346.

The spelling of 221451404 in words is "two hundred twenty-one million, four hundred fifty-one thousand, four hundred four".