81844245 has 24 divisors (see below), whose sum is σ = 162130176. Its totient is φ = 37414368.

The previous prime is 81844199. The next prime is 81844277. The reversal of 81844245 is 54244818.

It is not a de Polignac number, because 81844245 - 2⁶ = 81844181 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 129597 + ... + 130226.

It is an arithmetic number, because the mean of its divisors is an integer number (6755424).

Almost surely, 2^81844245 is an apocalyptic number.

It is an amenable number.

81844245 is a deficient number, since it is larger than the sum of its proper divisors (80285931).

81844245 is a wasteful number, since it uses less digits than its factorization.

81844245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 259841 (or 259838 counting only the distinct ones).

The product of its digits is 40960, while the sum is 36.

The square root of 81844245 is about 9046.7809191999. The cubic root of 81844245 is about 434.1729032096.

The spelling of 81844245 in words is "eighty-one million, eight hundred forty-four thousand, two hundred forty-five".