164778920505218 has 16 divisors (see below), whose sum is σ = 252959887641120. Its totient is φ = 80459615609856.

The previous prime is 164778920505203. The next prime is 164778920505239. The reversal of 164778920505218 is 812505029877461.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 163908863 + ... + 164911106.

It is an arithmetic number, because the mean of its divisors is an integer number (15809992977570).

Almost surely, 2^{164778920505218} is an apocalyptic number.

164778920505218 is a deficient number, since it is larger than the sum of its proper divisors (88180967135902).

164778920505218 is a wasteful number, since it uses less digits than its factorization.

164778920505218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 328825841.

The product of its (nonzero) digits is 67737600, while the sum is 65.

The spelling of 164778920505218 in words is "one hundred sixty-four trillion, seven hundred seventy-eight billion, nine hundred twenty million, five hundred five thousand, two hundred eighteen".