21121151423223 has 4 divisors (see below), whose sum is σ = 28161535230968. Its totient is φ = 14080767615480.

The previous prime is 21121151423161. The next prime is 21121151423227. The reversal of 21121151423223 is 32232415112112.

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

It is not a de Polignac number, because 21121151423223 - 2¹⁷ = 21121151292151 is a prime.

It is a super-2 number, since 2×21121151423223² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21121151423227) 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, 3520191903868 + ... + 3520191903873.

It is an arithmetic number, because the mean of its divisors is an integer number (7040383807742).

Almost surely, 2^{21121151423223} is an apocalyptic number.

21121151423223 is a deficient number, since it is larger than the sum of its proper divisors (7040383807745).

21121151423223 is an equidigital number, since it uses as much as digits as its factorization.

21121151423223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7040383807744.

The product of its digits is 5760, while the sum is 30.

Adding to 21121151423223 its reverse (32232415112112), we get a palindrome (53353566535335).

The spelling of 21121151423223 in words is "twenty-one trillion, one hundred twenty-one billion, one hundred fifty-one million, four hundred twenty-three thousand, two hundred twenty-three".