221306723 has 8 divisors (see below), whose sum is σ = 241536816. Its totient is φ = 201095200.

The previous prime is 221306693. The next prime is 221306749. The reversal of 221306723 is 327603122.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 221306723 - 2²² = 217112419 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221306692 and 221306701.

It is not an unprimeable number, because it can be changed into a prime (221306753) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35165 + ... + 40977.

It is an arithmetic number, because the mean of its divisors is an integer number (30192102).

Almost surely, 2^221306723 is an apocalyptic number.

221306723 is a deficient number, since it is larger than the sum of its proper divisors (20230093).

221306723 is a wasteful number, since it uses less digits than its factorization.

221306723 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9285.

The product of its (nonzero) digits is 3024, while the sum is 26.

The square root of 221306723 is about 14876.3813812365. The cubic root of 221306723 is about 604.8739331617.

Adding to 221306723 its reverse (327603122), we get a palindrome (548909845).

The spelling of 221306723 in words is "two hundred twenty-one million, three hundred six thousand, seven hundred twenty-three".