21010021223 has 2 divisors, whose sum is σ = 21010021224. Its totient is φ = 21010021222.

The previous prime is 21010021213. The next prime is 21010021231. The reversal of 21010021223 is 32212001012.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21010021223 - 2¹⁴ = 21010004839 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21010021198 and 21010021207.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21010021213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505010611 + 10505010612.

It is an arithmetic number, because the mean of its divisors is an integer number (10505010612).

Almost surely, 2^21010021223 is an apocalyptic number.

21010021223 is a deficient number, since it is larger than the sum of its proper divisors (1).

21010021223 is an equidigital number, since it uses as much as digits as its factorization.

21010021223 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48, while the sum is 14.

Adding to 21010021223 its reverse (32212001012), we get a palindrome (53222022235).

The spelling of 21010021223 in words is "twenty-one billion, ten million, twenty-one thousand, two hundred twenty-three".