21121220231223 has 32 divisors (see below), whose sum is σ = 32243095272960. Its totient is φ = 12047379333120.

The previous prime is 21121220231213. The next prime is 21121220231227. The reversal of 21121220231223 is 32213202212112.

It is not a de Polignac number, because 21121220231223 - 2¹² = 21121220227127 is a prime.

It is a super-2 number, since 2×21121220231223² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21121220231193 and 21121220231202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21121220231227) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 233263623 + ... + 233354151.

It is an arithmetic number, because the mean of its divisors is an integer number (1007596727280).

Almost surely, 2^{21121220231223} is an apocalyptic number.

21121220231223 is a deficient number, since it is larger than the sum of its proper divisors (11121875041737).

21121220231223 is a wasteful number, since it uses less digits than its factorization.

21121220231223 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110567.

The product of its (nonzero) digits is 1152, while the sum is 24.

Adding to 21121220231223 its reverse (32213202212112), we get a palindrome (53334422443335).

The spelling of 21121220231223 in words is "twenty-one trillion, one hundred twenty-one billion, two hundred twenty million, two hundred thirty-one thousand, two hundred twenty-three".