220323661 has 4 divisors (see below), whose sum is σ = 220526332. Its totient is φ = 220120992.

The previous prime is 220323659. The next prime is 220323667. The reversal of 220323661 is 166323022.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 184443561 + 35880100 = 13581^2 + 5990^2 .

It is a cyclic number.

It is not a de Polignac number, because 220323661 - 2¹ = 220323659 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (220323667) 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, 99696 + ... + 101881.

It is an arithmetic number, because the mean of its divisors is an integer number (55131583).

Almost surely, 2^220323661 is an apocalyptic number.

It is an amenable number.

220323661 is a deficient number, since it is larger than the sum of its proper divisors (202671).

220323661 is a wasteful number, since it uses less digits than its factorization.

220323661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 202670.

The product of its (nonzero) digits is 2592, while the sum is 25.

The square root of 220323661 is about 14843.3035743395. The cubic root of 220323661 is about 603.9769710750.

Adding to 220323661 its reverse (166323022), we get a palindrome (386646683).

The spelling of 220323661 in words is "two hundred twenty million, three hundred twenty-three thousand, six hundred sixty-one".