164393778 has 16 divisors (see below), whose sum is σ = 329023296. Its totient is φ = 54758640.

The previous prime is 164393759. The next prime is 164393783. The reversal of 164393778 is 877393461.

164393778 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

164393778 is a nontrivial binomial coefficient, being equal to C(18133, 2).

It is a super-2 number, since 2×164393778² = 54050628490226568, which contains 22 as substring.

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, 1 + ... + 18132.

It is an arithmetic number, because the mean of its divisors is an integer number (20563956).

Almost surely, 2^164393778 is an apocalyptic number.

164393778 is the 18132-nd triangular number.

164393778 is an abundant number, since it is smaller than the sum of its proper divisors (164629518).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

164393778 is a wasteful number, since it uses less digits than its factorization.

164393778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19649.

The product of its digits is 762048, while the sum is 48.

The square root of 164393778 is about 12821.6137049905. The cubic root of 164393778 is about 547.8081116392.

The spelling of 164393778 in words is "one hundred sixty-four million, three hundred ninety-three thousand, seven hundred seventy-eight".