81042818 has 8 divisors (see below), whose sum is σ = 121676412. Its totient is φ = 40484016.

The previous prime is 81042817. The next prime is 81042827. The reversal of 81042818 is 81824018.

It can be written as a sum of positive squares in 2 ways, for example, as 80048809 + 994009 = 8947^2 + 997^2 .

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

It is a super-2 number, since 2×81042818² = 13135876698762248, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81042811) 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, 15905 + ... + 20372.

Almost surely, 2^81042818 is an apocalyptic number.

81042818 is a deficient number, since it is larger than the sum of its proper divisors (40633594).

81042818 is a wasteful number, since it uses less digits than its factorization.

81042818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37396.

The product of its (nonzero) digits is 4096, while the sum is 32.

The square root of 81042818 is about 9002.3784634951. The cubic root of 81042818 is about 432.7510974673.

The spelling of 81042818 in words is "eighty-one million, forty-two thousand, eight hundred eighteen".