221690384 has 60 divisors (see below), whose sum is σ = 457978500. Its totient is φ = 103832064.

The previous prime is 221690363. The next prime is 221690407. The reversal of 221690384 is 483096122.

It can be written as a sum of positive squares in 6 ways, for example, as 68425984 + 153264400 = 8272^2 + 12380^2 .

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 in 11 ways as a sum of consecutive naturals, for example, 635042 + ... + 635390.

It is an arithmetic number, because the mean of its divisors is an integer number (7632975).

Almost surely, 2^221690384 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221690384, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (228989250).

221690384 is an abundant number, since it is smaller than the sum of its proper divisors (236288116).

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

221690384 is a wasteful number, since it uses less digits than its factorization.

221690384 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 460 (or 417 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 35.

The square root of 221690384 is about 14889.2707679053. The cubic root of 221690384 is about 605.2232711892.

The spelling of 221690384 in words is "two hundred twenty-one million, six hundred ninety thousand, three hundred eighty-four".