81184438 has 24 divisors (see below), whose sum is σ = 126630000. Its totient is φ = 39032928.

The previous prime is 81184409. The next prime is 81184459. The reversal of 81184438 is 83448118.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a junction number, because it is equal to n+sod(n) for n = 81184397 and 81184406.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 407863 + ... + 408061.

It is an arithmetic number, because the mean of its divisors is an integer number (5276250).

Almost surely, 2^81184438 is an apocalyptic number.

81184438 is a deficient number, since it is larger than the sum of its proper divisors (45445562).

81184438 is a wasteful number, since it uses less digits than its factorization.

81184438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 424 (or 387 counting only the distinct ones).

The product of its digits is 24576, while the sum is 37.

The square root of 81184438 is about 9010.2407293035. The cubic root of 81184438 is about 433.0030241563.

The spelling of 81184438 in words is "eighty-one million, one hundred eighty-four thousand, four hundred thirty-eight".