20122112111221 has 4 divisors (see below), whose sum is σ = 20123350487500. Its totient is φ = 20120873734944.

The previous prime is 20122112111203. The next prime is 20122112111281. The reversal of 20122112111221 is 12211121122102.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 9116232876100 + 11005879235121 = 3019310^2 + 3317511^2 .

It is a cyclic number.

It is not a de Polignac number, because 20122112111221 - 2⁷ = 20122112111093 is a prime.

It is a super-2 number, since 2×20122112111221² (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 (20122112111281) 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, 619163766 + ... + 619196263.

It is an arithmetic number, because the mean of its divisors is an integer number (5030837621875).

Almost surely, 2^{20122112111221} is an apocalyptic number.

It is an amenable number.

20122112111221 is a deficient number, since it is larger than the sum of its proper divisors (1238376279).

20122112111221 is a wasteful number, since it uses less digits than its factorization.

20122112111221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1238376278.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 20122112111221 its reverse (12211121122102), we get a palindrome (32333233233323).

The spelling of 20122112111221 in words is "twenty trillion, one hundred twenty-two billion, one hundred twelve million, one hundred eleven thousand, two hundred twenty-one".