221084278416 has 225 divisors, whose sum is σ = 659511851691. Its totient is φ = 71499884544.

The previous prime is 221084278361. The next prime is 221084278423. The reversal of 221084278416 is 614872480122.

The square root of 221084278416 is 470196.

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

221084278416 is a `hidden beast` number, since 2 + 210 + 8 + 427 + 8 + 4 + 1 + 6 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 27554672016 + 193529606400 = 165996^2 + 439920^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 626300896 + ... + 626301248.

Almost surely, 2^221084278416 is an apocalyptic number.

221084278416 is the 470196-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221084278416

221084278416 is an abundant number, since it is smaller than the sum of its proper divisors (438427573275).

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

221084278416 is an frugal number, since it uses more digits than its factorization.

221084278416 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 800 (or 395 counting only the distinct ones).

The product of its (nonzero) digits is 344064, while the sum is 45.

It can be divided in two parts, 221084 and 278416, that added together give a triangular number (499500 = T₉₉₉).

The spelling of 221084278416 in words is "two hundred twenty-one billion, eighty-four million, two hundred seventy-eight thousand, four hundred sixteen".