81214535787 has 16 divisors (see below), whose sum is σ = 135005981952. Its totient is φ = 42189369120.

The previous prime is 81214535783. The next prime is 81214535827. The reversal of 81214535787 is 78753541218.

It is not a de Polignac number, because 81214535787 - 2² = 81214535783 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81214535783) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 175788808 + ... + 175789269.

It is an arithmetic number, because the mean of its divisors is an integer number (8437873872).

Almost surely, 2^81214535787 is an apocalyptic number.

81214535787 is a deficient number, since it is larger than the sum of its proper divisors (53791446165).

81214535787 is a wasteful number, since it uses less digits than its factorization.

81214535787 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 351578098.

The product of its digits is 1881600, while the sum is 51.

The spelling of 81214535787 in words is "eighty-one billion, two hundred fourteen million, five hundred thirty-five thousand, seven hundred eighty-seven".