20402220121 has 16 divisors (see below), whose sum is σ = 21698185600. Its totient is φ = 19128711168.

The previous prime is 20402220089. The next prime is 20402220131. The reversal of 20402220121 is 12102220402.

It is not a de Polignac number, because 20402220121 - 2⁵ = 20402220089 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20402220095 and 20402220104.

It is not an unprimeable number, because it can be changed into a prime (20402220131) 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, 5260435 + ... + 5264311.

It is an arithmetic number, because the mean of its divisors is an integer number (1356136600).

Almost surely, 2^20402220121 is an apocalyptic number.

It is an amenable number.

20402220121 is a deficient number, since it is larger than the sum of its proper divisors (1295965479).

20402220121 is a wasteful number, since it uses less digits than its factorization.

20402220121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6688.

The product of its (nonzero) digits is 128, while the sum is 16.

Adding to 20402220121 its reverse (12102220402), we get a palindrome (32504440523).

The spelling of 20402220121 in words is "twenty billion, four hundred two million, two hundred twenty thousand, one hundred twenty-one".