81887183 has 12 divisors (see below), whose sum is σ = 95991192. Its totient is φ = 69647760.

The previous prime is 81887167. The next prime is 81887189. The reversal of 81887183 is 38178818.

It is not a de Polignac number, because 81887183 - 2⁴ = 81887167 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81887189) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 41 + ... + 12797.

It is an arithmetic number, because the mean of its divisors is an integer number (7999266).

Almost surely, 2^81887183 is an apocalyptic number.

81887183 is a deficient number, since it is larger than the sum of its proper divisors (14104009).

81887183 is a wasteful number, since it uses less digits than its factorization.

81887183 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12902 (or 12895 counting only the distinct ones).

The product of its digits is 86016, while the sum is 44.

The square root of 81887183 is about 9049.1537173373. The cubic root of 81887183 is about 434.2488167408.

The spelling of 81887183 in words is "eighty-one million, eight hundred eighty-seven thousand, one hundred eighty-three".