164049381 has 20 divisors (see below), whose sum is σ = 246005100. Its totient is φ = 108945216.

The previous prime is 164049349. The next prime is 164049397. The reversal of 164049381 is 183940461.

164049381 is a `hidden beast` number, since 1 + 640 + 4 + 9 + 3 + 8 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 29257281 + 134792100 = 5409^2 + 11610^2 .

It is not a de Polignac number, because 164049381 - 2⁵ = 164049349 is a prime.

It is a super-2 number, since 2×164049381² = 53824398812966322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (164049341) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 18025 + ... + 25553.

It is an arithmetic number, because the mean of its divisors is an integer number (12300255).

Almost surely, 2^164049381 is an apocalyptic number.

It is an amenable number.

164049381 is a deficient number, since it is larger than the sum of its proper divisors (81955719).

164049381 is an equidigital number, since it uses as much as digits as its factorization.

164049381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7810 (or 7801 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 164049381 is about 12808.1763338892. The cubic root of 164049381 is about 547.4253003735.

The spelling of 164049381 in words is "one hundred sixty-four million, forty-nine thousand, three hundred eighty-one".