221261730 has 32 divisors (see below), whose sum is σ = 531430848. Its totient is φ = 58958400.

The previous prime is 221261717. The next prime is 221261767. The reversal of 221261730 is 37162122.

It is a self number, because there is not a number n which added to its sum of digits gives 221261730.

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 15 ways as a sum of consecutive naturals, for example, 62200 + ... + 65660.

It is an arithmetic number, because the mean of its divisors is an integer number (16607214).

Almost surely, 2^221261730 is an apocalyptic number.

221261730 is an abundant number, since it is smaller than the sum of its proper divisors (310169118).

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

221261730 is a wasteful number, since it uses less digits than its factorization.

221261730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5602.

The product of its (nonzero) digits is 1008, while the sum is 24.

The square root of 221261730 is about 14874.8690750541. The cubic root of 221261730 is about 604.8329388694.

The spelling of 221261730 in words is "two hundred twenty-one million, two hundred sixty-one thousand, seven hundred thirty".