81810246 has 32 divisors (see below), whose sum is σ = 187361280. Its totient is φ = 23328576.

The previous prime is 81810233. The next prime is 81810259. The reversal of 81810246 is 64201818.

It is an interprime number because it is at equal distance from previous prime (81810233) and next prime (81810259).

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 15 ways as a sum of consecutive naturals, for example, 23890 + ... + 27098.

It is an arithmetic number, because the mean of its divisors is an integer number (5855040).

Almost surely, 2^81810246 is an apocalyptic number.

81810246 is an abundant number, since it is smaller than the sum of its proper divisors (105551034).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81810246 is a wasteful number, since it uses less digits than its factorization.

81810246 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3828.

The product of its (nonzero) digits is 3072, while the sum is 30.

The square root of 81810246 is about 9044.9016578402. The cubic root of 81810246 is about 434.1127748156.

The spelling of 81810246 in words is "eighty-one million, eight hundred ten thousand, two hundred forty-six".