221012916 has 12 divisors (see below), whose sum is σ = 515696832. Its totient is φ = 73670968.

The previous prime is 221012881. The next prime is 221012917. The reversal of 221012916 is 619210122.

221012916 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221012917) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9208860 + ... + 9208883.

It is an arithmetic number, because the mean of its divisors is an integer number (42974736).

Almost surely, 2^221012916 is an apocalyptic number.

It is an amenable number.

221012916 is an abundant number, since it is smaller than the sum of its proper divisors (294683916).

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

221012916 is a wasteful number, since it uses less digits than its factorization.

221012916 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18417750 (or 18417748 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 24.

The square root of 221012916 is about 14866.5031530619. The cubic root of 221012916 is about 604.6061375630.

The spelling of 221012916 in words is "two hundred twenty-one million, twelve thousand, nine hundred sixteen".