220250721 has 4 divisors (see below), whose sum is σ = 293667632. Its totient is φ = 146833812.

The previous prime is 220250699. The next prime is 220250749. The reversal of 220250721 is 127052022.

It is a happy number.

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 not a de Polignac number, because 220250721 - 2⁹ = 220250209 is a prime.

It is a super-3 number, since 3×220250721³ (a number of 26 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (220250791) 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, 36708451 + ... + 36708456.

It is an arithmetic number, because the mean of its divisors is an integer number (73416908).

Almost surely, 2^220250721 is an apocalyptic number.

It is an amenable number.

220250721 is a deficient number, since it is larger than the sum of its proper divisors (73416911).

220250721 is an equidigital number, since it uses as much as digits as its factorization.

220250721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73416910.

The product of its (nonzero) digits is 560, while the sum is 21.

The square root of 220250721 is about 14840.8463707431. The cubic root of 220250721 is about 603.9103131674.

The spelling of 220250721 in words is "two hundred twenty million, two hundred fifty thousand, seven hundred twenty-one".