221021023 has 8 divisors (see below), whose sum is σ = 222549120. Its totient is φ = 219497880.

The previous prime is 221020957. The next prime is 221021033. The reversal of 221021023 is 320120122.

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 221021023 - 2⁹ = 221020511 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221020994 and 221021012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221021033) 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, 135708 + ... + 137326.

It is an arithmetic number, because the mean of its divisors is an integer number (27818640).

Almost surely, 2^221021023 is an apocalyptic number.

221021023 is a deficient number, since it is larger than the sum of its proper divisors (1528097).

221021023 is a wasteful number, since it uses less digits than its factorization.

221021023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2477.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 221021023 is about 14866.7758105112. The cubic root of 221021023 is about 604.6135300148.

Adding to 221021023 its reverse (320120122), we get a palindrome (541141145).

Subtracting 221021023 from its reverse (320120122), we obtain a palindrome (99099099).

The spelling of 221021023 in words is "two hundred twenty-one million, twenty-one thousand, twenty-three".