221213023 has 4 divisors (see below), whose sum is σ = 224839528. Its totient is φ = 217586520.

The previous prime is 221213021. The next prime is 221213039. The reversal of 221213023 is 320312122.

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

It is a cyclic number.

It is not a de Polignac number, because 221213023 - 2¹ = 221213021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221212988 and 221213006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221213021) 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, 1813161 + ... + 1813282.

It is an arithmetic number, because the mean of its divisors is an integer number (56209882).

Almost surely, 2^221213023 is an apocalyptic number.

221213023 is a deficient number, since it is larger than the sum of its proper divisors (3626505).

221213023 is an equidigital number, since it uses as much as digits as its factorization.

221213023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3626504.

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 221213023 is about 14873.2317604480. The cubic root of 221213023 is about 604.7885543903.

Adding to 221213023 its reverse (320312122), we get a palindrome (541525145).

Subtracting 221213023 from its reverse (320312122), we obtain a palindrome (99099099).

The spelling of 221213023 in words is "two hundred twenty-one million, two hundred thirteen thousand, twenty-three".