21221212121023 has 8 divisors (see below), whose sum is σ = 21747052915328. Its totient is φ = 20701521511704.

The previous prime is 21221212120963. The next prime is 21221212121063. The reversal of 21221212121023 is 32012121212212.

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

It is a cyclic number.

It is not a de Polignac number, because 21221212121023 - 2²⁵ = 21221178566591 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21221212120985 and 21221212121003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221212121063) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1537539261 + ... + 1537553062.

It is an arithmetic number, because the mean of its divisors is an integer number (2718381614416).

Almost surely, 2^{21221212121023} is an apocalyptic number.

21221212121023 is a deficient number, since it is larger than the sum of its proper divisors (525840794305).

21221212121023 is a wasteful number, since it uses less digits than its factorization.

21221212121023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3075092493.

The product of its (nonzero) digits is 384, while the sum is 22.

Adding to 21221212121023 its reverse (32012121212212), we get a palindrome (53233333333235).

The spelling of 21221212121023 in words is "twenty-one trillion, two hundred twenty-one billion, two hundred twelve million, one hundred twenty-one thousand, twenty-three".