81333198 has 48 divisors (see below), whose sum is σ = 186541056. Its totient is φ = 25557840.

The previous prime is 81333173. The next prime is 81333227. The reversal of 81333198 is 89133318.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 28011 + ... + 30777.

It is an arithmetic number, because the mean of its divisors is an integer number (3886272).

Almost surely, 2^81333198 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81333198, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (93270528).

81333198 is an abundant number, since it is smaller than the sum of its proper divisors (105207858).

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

81333198 is a wasteful number, since it uses less digits than its factorization.

81333198 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2869 (or 2866 counting only the distinct ones).

The product of its digits is 15552, while the sum is 36.

The square root of 81333198 is about 9018.4920025468. The cubic root of 81333198 is about 433.2673368263.

The spelling of 81333198 in words is "eighty-one million, three hundred thirty-three thousand, one hundred ninety-eight".