181394641 has 4 divisors (see below), whose sum is σ = 192064932. Its totient is φ = 170724352.

The previous prime is 181394621. The next prime is 181394651. The reversal of 181394641 is 146493181.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 166410000 + 14984641 = 12900^2 + 3871^2 .

It is a cyclic number.

It is not a de Polignac number, because 181394641 - 2⁷ = 181394513 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 181394641.

It is not an unprimeable number, because it can be changed into a prime (181394621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5335120 + ... + 5335153.

It is an arithmetic number, because the mean of its divisors is an integer number (48016233).

Almost surely, 2^181394641 is an apocalyptic number.

It is an amenable number.

181394641 is a deficient number, since it is larger than the sum of its proper divisors (10670291).

181394641 is a wasteful number, since it uses less digits than its factorization.

181394641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10670290.

The product of its digits is 20736, while the sum is 37.

The square root of 181394641 is about 13468.2827784391. The cubic root of 181394641 is about 566.0760978065.

The spelling of 181394641 in words is "one hundred eighty-one million, three hundred ninety-four thousand, six hundred forty-one".