20200021121 has 6 divisors (see below), whose sum is σ = 23497983810. Its totient is φ = 17314303776.

The previous prime is 20200021117. The next prime is 20200021123. The reversal of 20200021121 is 12112000202.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 10263918721 + 9936102400 = 101311^2 + 99680^2 .

It is not a de Polignac number, because 20200021121 - 2² = 20200021117 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20200021123) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 206122616 + ... + 206122713.

It is an arithmetic number, because the mean of its divisors is an integer number (3916330635).

Almost surely, 2^20200021121 is an apocalyptic number.

It is an amenable number.

20200021121 is a deficient number, since it is larger than the sum of its proper divisors (3297962689).

20200021121 is an equidigital number, since it uses as much as digits as its factorization.

20200021121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 412245343 (or 412245336 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 20200021121 its reverse (12112000202), we get a palindrome (32312021323).

The spelling of 20200021121 in words is "twenty billion, two hundred million, twenty-one thousand, one hundred twenty-one".