221916956 has 6 divisors (see below), whose sum is σ = 388354680. Its totient is φ = 110958476.

The previous prime is 221916953. The next prime is 221916967. The reversal of 221916956 is 659619122.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221916953) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27739616 + ... + 27739623.

It is an arithmetic number, because the mean of its divisors is an integer number (64725780).

Almost surely, 2^221916956 is an apocalyptic number.

It is an amenable number.

221916956 is a deficient number, since it is larger than the sum of its proper divisors (166437724).

221916956 is a wasteful number, since it uses less digits than its factorization.

221916956 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55479243 (or 55479241 counting only the distinct ones).

The product of its digits is 58320, while the sum is 41.

The square root of 221916956 is about 14896.8773909165. The cubic root of 221916956 is about 605.4293844114.

The spelling of 221916956 in words is "two hundred twenty-one million, nine hundred sixteen thousand, nine hundred fifty-six".