81408538086 has 16 divisors (see below), whose sum is σ = 163286293824. Its totient is φ = 27057976424.

The previous prime is 81408538049. The next prime is 81408538091. The reversal of 81408538086 is 68083580418.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19548480 + ... + 19552643.

It is an arithmetic number, because the mean of its divisors is an integer number (10205393364).

Almost surely, 2^81408538086 is an apocalyptic number.

81408538086 is an abundant number, since it is smaller than the sum of its proper divisors (81877755738).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81408538086 is a wasteful number, since it uses less digits than its factorization.

81408538086 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39101475.

The product of its (nonzero) digits is 1474560, while the sum is 51.

The spelling of 81408538086 in words is "eighty-one billion, four hundred eight million, five hundred thirty-eight thousand, eighty-six".