81199481 has 8 divisors (see below), whose sum is σ = 89649504. Its totient is φ = 72927520.

The previous prime is 81199451. The next prime is 81199501. The reversal of 81199481 is 18499118.

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

It is a cyclic number.

It is not a de Polignac number, because 81199481 - 2²⁶ = 14090617 is a prime.

It is a super-2 number, since 2×81199481² = 13186711429338722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81199451) 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 7 ways as a sum of consecutive naturals, for example, 43556 + ... + 45381.

It is an arithmetic number, because the mean of its divisors is an integer number (11206188).

Almost surely, 2^81199481 is an apocalyptic number.

It is an amenable number.

81199481 is a deficient number, since it is larger than the sum of its proper divisors (8450023).

81199481 is a wasteful number, since it uses less digits than its factorization.

81199481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89031.

The product of its digits is 20736, while the sum is 41.

The square root of 81199481 is about 9011.0754630066. The cubic root of 81199481 is about 433.0297668112.

The spelling of 81199481 in words is "eighty-one million, one hundred ninety-nine thousand, four hundred eighty-one".