81388513286 has 8 divisors (see below), whose sum is σ = 123341355480. Its totient is φ = 40274728128.

The previous prime is 81388513279. The next prime is 81388513343. The reversal of 81388513286 is 68231588318.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 209764016 + ... + 209764403.

It is an arithmetic number, because the mean of its divisors is an integer number (15417669435).

Almost surely, 2^81388513286 is an apocalyptic number.

81388513286 is a deficient number, since it is larger than the sum of its proper divisors (41952842194).

81388513286 is a wasteful number, since it uses less digits than its factorization.

81388513286 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 419528518.

The product of its digits is 2211840, while the sum is 53.

The spelling of 81388513286 in words is "eighty-one billion, three hundred eighty-eight million, five hundred thirteen thousand, two hundred eighty-six".