220729321 has 4 divisors (see below), whose sum is σ = 230326272. Its totient is φ = 211132372.

The previous prime is 220729307. The next prime is 220729349. The reversal of 220729321 is 123927022.

220729321 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 220729321 - 2⁷ = 220729193 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 220729321.

It is not an unprimeable number, because it can be changed into a prime (220729361) 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, 4798441 + ... + 4798486.

It is an arithmetic number, because the mean of its divisors is an integer number (57581568).

Almost surely, 2^220729321 is an apocalyptic number.

It is an amenable number.

220729321 is a deficient number, since it is larger than the sum of its proper divisors (9596951).

220729321 is an equidigital number, since it uses as much as digits as its factorization.

220729321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9596950.

The product of its (nonzero) digits is 3024, while the sum is 28.

The square root of 220729321 is about 14856.9620380480. The cubic root of 220729321 is about 604.3474246767.

The spelling of 220729321 in words is "two hundred twenty million, seven hundred twenty-nine thousand, three hundred twenty-one".