20403040432121 has 16 divisors (see below), whose sum is σ = 21126924046800. Its totient is φ = 19680519522048.

The previous prime is 20403040432081. The next prime is 20403040432153. The reversal of 20403040432121 is 12123404030402.

It can be written as a sum of positive squares in 8 ways, for example, as 329604025 + 20402710828096 = 18155^2 + 4516936^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20403040432121 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20403040332121) 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, 162261551 + ... + 162387243.

It is an arithmetic number, because the mean of its divisors is an integer number (1320432752925).

Almost surely, 2^{20403040432121} is an apocalyptic number.

It is an amenable number.

20403040432121 is a deficient number, since it is larger than the sum of its proper divisors (723883614679).

20403040432121 is a wasteful number, since it uses less digits than its factorization.

20403040432121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131068.

The product of its (nonzero) digits is 4608, while the sum is 26.

Adding to 20403040432121 its reverse (12123404030402), we get a palindrome (32526444462523).

The spelling of 20403040432121 in words is "twenty trillion, four hundred three billion, forty million, four hundred thirty-two thousand, one hundred twenty-one".