81988876 has 18 divisors (see below), whose sum is σ = 151432260. Its totient is φ = 38836152.

The previous prime is 81988853. The next prime is 81988897. The reversal of 81988876 is 67888918.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 26946 + ... + 29833.

Almost surely, 2^81988876 is an apocalyptic number.

It is an amenable number.

81988876 is a deficient number, since it is larger than the sum of its proper divisors (69443384).

81988876 is a wasteful number, since it uses less digits than its factorization.

81988876 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56821 (or 56800 counting only the distinct ones).

The product of its digits is 1548288, while the sum is 55.

The square root of 81988876 is about 9054.7708971569. The cubic root of 81988876 is about 434.4285021551.

The spelling of 81988876 in words is "eighty-one million, nine hundred eighty-eight thousand, eight hundred seventy-six".