221278041604 has 27 divisors (see below), whose sum is σ = 408723140007. Its totient is φ = 104807447208.

The previous prime is 221278041601. The next prime is 221278041631. The reversal of 221278041604 is 406140872122.

The square root of 221278041604 is 470402.

It is a perfect power (a square), and thus also a powerful number.

It is a super-2 number, since 2×221278041604² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221278041601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 17869087 + ... + 17881465.

Almost surely, 2^221278041604 is an apocalyptic number.

221278041604 is the 470402-nd square number.

It is an amenable number.

221278041604 is a deficient number, since it is larger than the sum of its proper divisors (187445098403).

221278041604 is an frugal number, since it uses more digits than its factorization.

221278041604 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24800 (or 12400 counting only the distinct ones).

The product of its (nonzero) digits is 43008, while the sum is 37.

The spelling of 221278041604 in words is "two hundred twenty-one billion, two hundred seventy-eight million, forty-one thousand, six hundred four".