81087788 has 24 divisors (see below), whose sum is σ = 150511200. Its totient is φ = 38142720.

The previous prime is 81087779. The next prime is 81087817. The reversal of 81087788 is 88778018.

It is an unprimeable number.

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, 1613 + ... + 12836.

It is an arithmetic number, because the mean of its divisors is an integer number (6271300).

Almost surely, 2^81087788 is an apocalyptic number.

It is an amenable number.

81087788 is a deficient number, since it is larger than the sum of its proper divisors (69423412).

81087788 is a wasteful number, since it uses less digits than its factorization.

81087788 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14537 (or 14535 counting only the distinct ones).

The product of its (nonzero) digits is 200704, while the sum is 47.

The square root of 81087788 is about 9004.8757903705. The cubic root of 81087788 is about 432.8311260205.

The spelling of 81087788 in words is "eighty-one million, eighty-seven thousand, seven hundred eighty-eight".