164778920505239 has 2 divisors, whose sum is σ = 164778920505240. Its totient is φ = 164778920505238.

The previous prime is 164778920505203. The next prime is 164778920505247. The reversal of 164778920505239 is 932505029877461.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 164778920505239 - 2¹⁶ = 164778920439703 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (164778920505289) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82389460252619 + 82389460252620.

It is an arithmetic number, because the mean of its divisors is an integer number (82389460252620).

It is a 1-persistent number, because it is pandigital, but 2⋅164778920505239 = 329557841010478 is not.

Almost surely, 2^{164778920505239} is an apocalyptic number.

164778920505239 is a deficient number, since it is larger than the sum of its proper divisors (1).

164778920505239 is an equidigital number, since it uses as much as digits as its factorization.

164778920505239 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 228614400, while the sum is 68.

The spelling of 164778920505239 in words is "one hundred sixty-four trillion, seven hundred seventy-eight billion, nine hundred twenty million, five hundred five thousand, two hundred thirty-nine".