21220552021123 has 24 divisors (see below), whose sum is σ = 26709978881040. Its totient is φ = 16710314281920.

The previous prime is 21220552021121. The next prime is 21220552021183. The reversal of 21220552021123 is 32112025502212.

It is a happy number.

It is not a de Polignac number, because 21220552021123 - 2¹ = 21220552021121 is a prime.

It is a super-2 number, since 2×21220552021123² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21220552021091 and 21220552021100.

It is not an unprimeable number, because it can be changed into a prime (21220552021121) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 78806988 + ... + 79075801.

It is an arithmetic number, because the mean of its divisors is an integer number (1112915786710).

Almost surely, 2^{21220552021123} is an apocalyptic number.

21220552021123 is a deficient number, since it is larger than the sum of its proper divisors (5489426859917).

21220552021123 is a wasteful number, since it uses less digits than its factorization.

21220552021123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 157883027 (or 157883020 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 28.

Adding to 21220552021123 its reverse (32112025502212), we get a palindrome (53332577523335).

The spelling of 21220552021123 in words is "twenty-one trillion, two hundred twenty billion, five hundred fifty-two million, twenty-one thousand, one hundred twenty-three".