81040818 has 32 divisors (see below), whose sum is σ = 165792960. Its totient is φ = 26400960.

The previous prime is 81040787. The next prime is 81040847. The reversal of 81040818 is 81804018.

It is a super-2 number, since 2×81040818² = 13135228364218248, which contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 64896 + ... + 66132.

It is an arithmetic number, because the mean of its divisors is an integer number (5181030).

Almost surely, 2^81040818 is an apocalyptic number.

81040818 is an abundant number, since it is smaller than the sum of its proper divisors (84752142).

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

81040818 is a wasteful number, since it uses less digits than its factorization.

81040818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1482.

The product of its (nonzero) digits is 2048, while the sum is 30.

The square root of 81040818 is about 9002.2673810546. The cubic root of 81040818 is about 432.7475375824.

The spelling of 81040818 in words is "eighty-one million, forty thousand, eight hundred eighteen".