81198271 has 8 divisors (see below), whose sum is σ = 101234304. Its totient is φ = 63271320.

The previous prime is 81198263. The next prime is 81198277. The reversal of 81198271 is 17289118.

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

It is not a de Polignac number, because 81198271 - 2³ = 81198263 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81198271.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81198277) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 527185 + ... + 527338.

It is an arithmetic number, because the mean of its divisors is an integer number (12654288).

Almost surely, 2^81198271 is an apocalyptic number.

81198271 is a deficient number, since it is larger than the sum of its proper divisors (20036033).

81198271 is a wasteful number, since it uses less digits than its factorization.

81198271 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1054541.

The product of its digits is 8064, while the sum is 37.

The square root of 81198271 is about 9011.0083231567. The cubic root of 81198271 is about 433.0276158589.

The spelling of 81198271 in words is "eighty-one million, one hundred ninety-eight thousand, two hundred seventy-one".