81404598 has 64 divisors (see below), whose sum is σ = 185068800. Its totient is φ = 23654400.

The previous prime is 81404593. The next prime is 81404621. The reversal of 81404598 is 89540418.

It is a super-3 number, since 3×81404598³ (a number of 25 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81404591) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 181078 + ... + 181526.

It is an arithmetic number, because the mean of its divisors is an integer number (2891700).

Almost surely, 2^81404598 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81404598, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (92534400).

81404598 is an abundant number, since it is smaller than the sum of its proper divisors (103664202).

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

81404598 is a wasteful number, since it uses less digits than its factorization.

81404598 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 573.

The product of its (nonzero) digits is 46080, while the sum is 39.

The square root of 81404598 is about 9022.4496673575. The cubic root of 81404598 is about 433.3940839219.

The spelling of 81404598 in words is "eighty-one million, four hundred four thousand, five hundred ninety-eight".