221815068 has 24 divisors (see below), whose sum is σ = 519796368. Its totient is φ = 73620096.

The previous prime is 221815049. The next prime is 221815079. The reversal of 221815068 is 860518122.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36871 + ... + 42462.

It is an arithmetic number, because the mean of its divisors is an integer number (21658182).

Almost surely, 2^221815068 is an apocalyptic number.

It is an amenable number.

221815068 is an abundant number, since it is smaller than the sum of its proper divisors (297981300).

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

221815068 is a wasteful number, since it uses less digits than its factorization.

221815068 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79573 (or 79571 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 33.

The square root of 221815068 is about 14893.4572212096. The cubic root of 221815068 is about 605.3367139620.

The spelling of 221815068 in words is "two hundred twenty-one million, eight hundred fifteen thousand, sixty-eight".