81184213 has 8 divisors (see below), whose sum is σ = 88631136. Its totient is φ = 73748400.

The previous prime is 81184199. The next prime is 81184219. The reversal of 81184213 is 31248118.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 81184213 - 2¹³ = 81176021 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81184219) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22770 + ... + 26092.

It is an arithmetic number, because the mean of its divisors is an integer number (11078892).

Almost surely, 2^81184213 is an apocalyptic number.

It is an amenable number.

81184213 is a deficient number, since it is larger than the sum of its proper divisors (7446923).

81184213 is a wasteful number, since it uses less digits than its factorization.

81184213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5555.

The product of its digits is 1536, while the sum is 28.

The square root of 81184213 is about 9010.2282435019. The cubic root of 81184213 is about 433.0026241380.

The spelling of 81184213 in words is "eighty-one million, one hundred eighty-four thousand, two hundred thirteen".