221026616 has 8 divisors (see below), whose sum is σ = 414424920. Its totient is φ = 110513304.

The previous prime is 221026591. The next prime is 221026649. The reversal of 221026616 is 616620122.

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×221026616² = 97705529960822912, which contains 22 as substring.

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 as a sum of consecutive naturals, namely, 13814156 + ... + 13814171.

It is an arithmetic number, because the mean of its divisors is an integer number (51803115).

Almost surely, 2^221026616 is an apocalyptic number.

It is an amenable number.

221026616 is a deficient number, since it is larger than the sum of its proper divisors (193398304).

221026616 is a wasteful number, since it uses less digits than its factorization.

221026616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27628333 (or 27628329 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 221026616 is about 14866.9639133214. The cubic root of 221026616 is about 604.6186299444.

Adding to 221026616 its reverse (616620122), we get a palindrome (837646738).

The spelling of 221026616 in words is "two hundred twenty-one million, twenty-six thousand, six hundred sixteen".