81838874 has 8 divisors (see below), whose sum is σ = 132201300. Its totient is φ = 37771776.

The previous prime is 81838849. The next prime is 81838879. The reversal of 81838874 is 47883818.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 75811849 + 6027025 = 8707^2 + 2455^2 .

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

It is not an unprimeable number, because it can be changed into a prime (81838879) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1573799 + ... + 1573850.

Almost surely, 2^81838874 is an apocalyptic number.

81838874 is a deficient number, since it is larger than the sum of its proper divisors (50362426).

81838874 is a wasteful number, since it uses less digits than its factorization.

81838874 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3147664.

The product of its digits is 344064, while the sum is 47.

The square root of 81838874 is about 9046.4840684102. The cubic root of 81838874 is about 434.1634055202.

The spelling of 81838874 in words is "eighty-one million, eight hundred thirty-eight thousand, eight hundred seventy-four".