81808888135 has 32 divisors (see below), whose sum is σ = 108474710400. Its totient is φ = 58844620800.

The previous prime is 81808888087. The next prime is 81808888157. The reversal of 81808888135 is 53188880818.

It is not a de Polignac number, because 81808888135 - 2⁹ = 81808887623 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81808888135.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1657291 + ... + 1705939.

It is an arithmetic number, because the mean of its divisors is an integer number (3389834700).

Almost surely, 2^81808888135 is an apocalyptic number.

81808888135 is a deficient number, since it is larger than the sum of its proper divisors (26665822265).

81808888135 is a wasteful number, since it uses less digits than its factorization.

81808888135 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49339.

The product of its (nonzero) digits is 3932160, while the sum is 58.

The spelling of 81808888135 in words is "eighty-one billion, eight hundred eight million, eight hundred eighty-eight thousand, one hundred thirty-five".