81149 has 4 divisors (see below), whose sum is σ = 85440. Its totient is φ = 76860.

The previous prime is 81131. The next prime is 81157. The reversal of 81149 is 94118.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 94118 = 2 ⋅47059.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81149 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 81149.

It is not an unprimeable number, because it can be changed into a prime (81119) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2117 + ... + 2154.

It is an arithmetic number, because the mean of its divisors is an integer number (21360).

2⁸¹¹⁴⁹ is an apocalyptic number.

It is an amenable number.

81149 is a deficient number, since it is larger than the sum of its proper divisors (4291).

81149 is a wasteful number, since it uses less digits than its factorization.

81149 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4290.

The product of its digits is 288, while the sum is 23.

The square root of 81149 is about 284.8666354630. The cubic root of 81149 is about 43.2940011282.

The spelling of 81149 in words is "eighty-one thousand, one hundred forty-nine".