204155517128219 has 2 divisors, whose sum is σ = 204155517128220. Its totient is φ = 204155517128218.

The previous prime is 204155517128141. The next prime is 204155517128221. The reversal of 204155517128219 is 912821715551402.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 204155517128219 - 2⁸ = 204155517127963 is a prime.

It is a super-2 number, since 2×204155517128219² (a number of 29 digits) contains 22 as substring.

It is a Sophie Germain prime.

Together with 204155517128221, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (204155517188219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102077758564109 + 102077758564110.

It is an arithmetic number, because the mean of its divisors is an integer number (102077758564110).

Almost surely, 2^{204155517128219} is an apocalyptic number.

204155517128219 is a deficient number, since it is larger than the sum of its proper divisors (1).

204155517128219 is an equidigital number, since it uses as much as digits as its factorization.

204155517128219 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2016000, while the sum is 53.

The spelling of 204155517128219 in words is "two hundred four trillion, one hundred fifty-five billion, five hundred seventeen million, one hundred twenty-eight thousand, two hundred nineteen".