221793390 has 384 divisors, whose sum is σ = 792529920. Its totient is φ = 43296768.

The previous prime is 221793379. The next prime is 221793401. The reversal of 221793390 is 93397122.

221793390 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (221793379) and next prime (221793401).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 3759181 + ... + 3759239.

It is an arithmetic number, because the mean of its divisors is an integer number (2063880).

Almost surely, 2^221793390 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221793390, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (396264960).

221793390 is an abundant number, since it is smaller than the sum of its proper divisors (570736530).

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

221793390 is a wasteful number, since it uses less digits than its factorization.

221793390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118 (or 106 counting only the distinct ones).

The product of its (nonzero) digits is 20412, while the sum is 36.

The square root of 221793390 is about 14892.7294341904. The cubic root of 221793390 is about 605.3169934550.

The spelling of 221793390 in words is "two hundred twenty-one million, seven hundred ninety-three thousand, three hundred ninety".