21021310223 has 8 divisors (see below), whose sum is σ = 21370502736. Its totient is φ = 20672265600.

The previous prime is 21021310217. The next prime is 21021310241. The reversal of 21021310223 is 32201312012.

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

It is not a de Polignac number, because 21021310223 - 2¹⁶ = 21021244687 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 (21021310523) 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, 270743 + ... + 339623.

It is an arithmetic number, because the mean of its divisors is an integer number (2671312842).

Almost surely, 2^21021310223 is an apocalyptic number.

21021310223 is a deficient number, since it is larger than the sum of its proper divisors (349192513).

21021310223 is an equidigital number, since it uses as much as digits as its factorization.

21021310223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73945.

The product of its (nonzero) digits is 144, while the sum is 17.

Adding to 21021310223 its reverse (32201312012), we get a palindrome (53222622235).

The spelling of 21021310223 in words is "twenty-one billion, twenty-one million, three hundred ten thousand, two hundred twenty-three".