81844923 has 4 divisors (see below), whose sum is σ = 109126568. Its totient is φ = 54563280.

The previous prime is 81844909. The next prime is 81844927. The reversal of 81844923 is 32944818.

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

It is not a de Polignac number, because 81844923 - 2¹² = 81840827 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81844927) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13640818 + ... + 13640823.

It is an arithmetic number, because the mean of its divisors is an integer number (27281642).

Almost surely, 2^81844923 is an apocalyptic number.

81844923 is a deficient number, since it is larger than the sum of its proper divisors (27281645).

81844923 is a wasteful number, since it uses less digits than its factorization.

81844923 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27281644.

The product of its digits is 55296, while the sum is 39.

The square root of 81844923 is about 9046.8183910146. The cubic root of 81844923 is about 434.1741021065.

The spelling of 81844923 in words is "eighty-one million, eight hundred forty-four thousand, nine hundred twenty-three".