221445402 has 16 divisors (see below), whose sum is σ = 443040192. Its totient is φ = 73790240.

The previous prime is 221445391. The next prime is 221445457. The reversal of 221445402 is 204544122.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25438 + ... + 33014.

It is an arithmetic number, because the mean of its divisors is an integer number (27690012).

Almost surely, 2^221445402 is an apocalyptic number.

221445402 is an abundant number, since it is smaller than the sum of its proper divisors (221594790).

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

221445402 is a wasteful number, since it uses less digits than its factorization.

221445402 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12453.

The product of its (nonzero) digits is 2560, while the sum is 24.

The square root of 221445402 is about 14881.0416974081. The cubic root of 221445402 is about 605.0002522595. Note that the first 3 decimals are identical.

Adding to 221445402 its reverse (204544122), we get a palindrome (425989524).

The spelling of 221445402 in words is "two hundred twenty-one million, four hundred forty-five thousand, four hundred two".