81624020186 has 16 divisors (see below), whose sum is σ = 124619560800. Its totient is φ = 40087658160.

The previous prime is 81624020173. The next prime is 81624020243. The reversal of 81624020186 is 68102042618.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 825920 + ... + 919451.

It is an arithmetic number, because the mean of its divisors is an integer number (7788722550).

Almost surely, 2^81624020186 is an apocalyptic number.

81624020186 is a deficient number, since it is larger than the sum of its proper divisors (42995540614).

81624020186 is a wasteful number, since it uses less digits than its factorization.

81624020186 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1745789.

The product of its (nonzero) digits is 36864, while the sum is 38.

The spelling of 81624020186 in words is "eighty-one billion, six hundred twenty-four million, twenty thousand, one hundred eighty-six".