20555442013 has 4 divisors (see below), whose sum is σ = 20556271260. Its totient is φ = 20554612768.

The previous prime is 20555442007. The next prime is 20555442023. The reversal of 20555442013 is 31024455502.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 9381472164 + 11173969849 = 96858^2 + 105707^2 .

It is a cyclic number.

It is not a de Polignac number, because 20555442013 - 2²⁹ = 20018571101 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20555442023) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 376258 + ... + 427411.

It is an arithmetic number, because the mean of its divisors is an integer number (5139067815).

Almost surely, 2^20555442013 is an apocalyptic number.

It is an amenable number.

20555442013 is a deficient number, since it is larger than the sum of its proper divisors (829247).

20555442013 is an equidigital number, since it uses as much as digits as its factorization.

20555442013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 829246.

The product of its (nonzero) digits is 24000, while the sum is 31.

Adding to 20555442013 its reverse (31024455502), we get a palindrome (51579897515).

The spelling of 20555442013 in words is "twenty billion, five hundred fifty-five million, four hundred forty-two thousand, thirteen".