21203112213123 has 16 divisors (see below), whose sum is σ = 28295594580000. Its totient is φ = 14123020713984.

The previous prime is 21203112213121. The next prime is 21203112213131. The reversal of 21203112213123 is 32131221130212.

It is not a de Polignac number, because 21203112213123 - 2¹ = 21203112213121 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21203112213093 and 21203112213102.

It is not an unprimeable number, because it can be changed into a prime (21203112213121) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 50875315 + ... + 51290387.

It is an arithmetic number, because the mean of its divisors is an integer number (1768474661250).

Almost surely, 2^{21203112213123} is an apocalyptic number.

21203112213123 is a deficient number, since it is larger than the sum of its proper divisors (7092482366877).

21203112213123 is a wasteful number, since it uses less digits than its factorization.

21203112213123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 429958.

The product of its (nonzero) digits is 864, while the sum is 24.

Adding to 21203112213123 its reverse (32131221130212), we get a palindrome (53334333343335).

The spelling of 21203112213123 in words is "twenty-one trillion, two hundred three billion, one hundred twelve million, two hundred thirteen thousand, one hundred twenty-three".