20213403121 has 16 divisors (see below), whose sum is σ = 21656088720. Its totient is φ = 18799165440.

The previous prime is 20213403047. The next prime is 20213403131. The reversal of 20213403121 is 12130431202.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 1854508096 + 18358895025 = 43064^2 + 135495^2 .

It is a cyclic number.

It is not a de Polignac number, because 20213403121 - 2²¹ = 20211305969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20213403131) 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, 3448225 + ... + 3454081.

It is an arithmetic number, because the mean of its divisors is an integer number (1353505545).

Almost surely, 2^20213403121 is an apocalyptic number.

It is an amenable number.

20213403121 is a deficient number, since it is larger than the sum of its proper divisors (1442685599).

20213403121 is a wasteful number, since it uses less digits than its factorization.

20213403121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8244.

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 20213403121 its reverse (12130431202), we get a palindrome (32343834323).

The spelling of 20213403121 in words is "twenty billion, two hundred thirteen million, four hundred three thousand, one hundred twenty-one".