20040121033813 has 2 divisors, whose sum is σ = 20040121033814. Its totient is φ = 20040121033812.

The previous prime is 20040121033811. The next prime is 20040121033819. The reversal of 20040121033813 is 31833012104002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11038188930129 + 9001932103684 = 3322377^2 + 3000322^2 .

It is a cyclic number.

It is not a de Polignac number, because 20040121033813 - 2¹ = 20040121033811 is a prime.

Together with 20040121033811, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20040121033811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10020060516906 + 10020060516907.

It is an arithmetic number, because the mean of its divisors is an integer number (10020060516907).

Almost surely, 2^{20040121033813} is an apocalyptic number.

It is an amenable number.

20040121033813 is a deficient number, since it is larger than the sum of its proper divisors (1).

20040121033813 is an equidigital number, since it uses as much as digits as its factorization.

20040121033813 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3456, while the sum is 28.

Adding to 20040121033813 its reverse (31833012104002), we get a palindrome (51873133137815).

The spelling of 20040121033813 in words is "twenty trillion, forty billion, one hundred twenty-one million, thirty-three thousand, eight hundred thirteen".