81398310 has 48 divisors (see below), whose sum is σ = 227254896. Its totient is φ = 18604992.

The previous prime is 81398267. The next prime is 81398323. The reversal of 81398310 is 1389318.

It is a super-2 number, since 2×81398310² = 13251369741712200, which contains 22 as substring.

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 23 ways as a sum of consecutive naturals, for example, 26217 + ... + 29156.

It is an arithmetic number, because the mean of its divisors is an integer number (4734477).

Almost surely, 2^81398310 is an apocalyptic number.

81398310 is an abundant number, since it is smaller than the sum of its proper divisors (145856586).

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

81398310 is a wasteful number, since it uses less digits than its factorization.

81398310 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55397 (or 55390 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 33.

The square root of 81398310 is about 9022.1011965063. The cubic root of 81398310 is about 433.3829246335.

The spelling of 81398310 in words is "eighty-one million, three hundred ninety-eight thousand, three hundred ten".