221906612 has 12 divisors (see below), whose sum is σ = 398832420. Its totient is φ = 107954496.

The previous prime is 221906603. The next prime is 221906621. The reversal of 221906612 is 216609122.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (221906603) and next prime (221906621).

It can be written as a sum of positive squares in 2 ways, for example, as 132112036 + 89794576 = 11494^2 + 9476^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 749537 + ... + 749832.

It is an arithmetic number, because the mean of its divisors is an integer number (33236035).

Almost surely, 2^221906612 is an apocalyptic number.

It is an amenable number.

221906612 is a deficient number, since it is larger than the sum of its proper divisors (176925808).

221906612 is a wasteful number, since it uses less digits than its factorization.

221906612 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1499410 (or 1499408 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 29.

The square root of 221906612 is about 14896.5302000164. The cubic root of 221906612 is about 605.4199775008.

The spelling of 221906612 in words is "two hundred twenty-one million, nine hundred six thousand, six hundred twelve".