81819258 has 16 divisors (see below), whose sum is σ = 163977696. Its totient is φ = 27216560.

The previous prime is 81819229. The next prime is 81819281. The reversal of 81819258 is 85291818.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10941 + ... + 16832.

It is an arithmetic number, because the mean of its divisors is an integer number (10248606).

Almost surely, 2^81819258 is an apocalyptic number.

81819258 is an abundant number, since it is smaller than the sum of its proper divisors (82158438).

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

81819258 is a wasteful number, since it uses less digits than its factorization.

81819258 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28269.

The product of its digits is 46080, while the sum is 42.

The square root of 81819258 is about 9045.3998253256. The cubic root of 81819258 is about 434.1287144682.

The spelling of 81819258 in words is "eighty-one million, eight hundred nineteen thousand, two hundred fifty-eight".