163778645 has 4 divisors (see below), whose sum is σ = 196534380. Its totient is φ = 131022912.

The previous prime is 163778633. The next prime is 163778759. The reversal of 163778645 is 546877361.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 546877361 = 19 ⋅28783019.

It can be written as a sum of positive squares in 2 ways, for example, as 23261329 + 140517316 = 4823^2 + 11854^2 .

It is a cyclic number.

It is not a de Polignac number, because 163778645 - 2²⁴ = 147001429 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 163778645.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16377860 + ... + 16377869.

It is an arithmetic number, because the mean of its divisors is an integer number (49133595).

Almost surely, 2^163778645 is an apocalyptic number.

It is an amenable number.

163778645 is a deficient number, since it is larger than the sum of its proper divisors (32755735).

163778645 is an equidigital number, since it uses as much as digits as its factorization.

163778645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32755734.

The product of its digits is 846720, while the sum is 47.

The square root of 163778645 is about 12797.6030958926. The cubic root of 163778645 is about 547.1239899982.

The spelling of 163778645 in words is "one hundred sixty-three million, seven hundred seventy-eight thousand, six hundred forty-five".