221302404 has 36 divisors (see below), whose sum is σ = 560363440. Its totient is φ = 73640880.

The previous prime is 221302391. The next prime is 221302409. The reversal of 221302404 is 404203122.

221302404 is digitally balanced in base 3 and base 9, because in such bases it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (18).

221302404 is strictly pandigital in base 9.

It is not an unprimeable number, because it can be changed into a prime (221302409) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17319 + ... + 27249.

Almost surely, 2^221302404 is an apocalyptic number.

It is an amenable number.

221302404 is an abundant number, since it is smaller than the sum of its proper divisors (339061036).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

221302404 is a wasteful number, since it uses less digits than its factorization.

221302404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10560 (or 10555 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

The square root of 221302404 is about 14876.2362175384. The cubic root of 221302404 is about 604.8699982495.

Adding to 221302404 its reverse (404203122), we get a palindrome (625505526).

The spelling of 221302404 in words is "two hundred twenty-one million, three hundred two thousand, four hundred four".