81115238 has 8 divisors (see below), whose sum is σ = 123667680. Its totient is φ = 39892680.

The previous prime is 81115219. The next prime is 81115241. The reversal of 81115238 is 83251118.

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

It is a self number, because there is not a number n which added to its sum of digits gives 81115238.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 332318 + ... + 332561.

It is an arithmetic number, because the mean of its divisors is an integer number (15458460).

Almost surely, 2^81115238 is an apocalyptic number.

81115238 is a deficient number, since it is larger than the sum of its proper divisors (42552442).

81115238 is a wasteful number, since it uses less digits than its factorization.

81115238 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 664942.

The product of its digits is 1920, while the sum is 29.

The square root of 81115238 is about 9006.3998356724. The cubic root of 81115238 is about 432.8799614628.

The spelling of 81115238 in words is "eighty-one million, one hundred fifteen thousand, two hundred thirty-eight".