81387956223 has 128 divisors (see below), whose sum is σ = 144169697280. Its totient is φ = 44971718400.

The previous prime is 81387956213. The next prime is 81387956231. The reversal of 81387956223 is 32265978318.

81387956223 is a `hidden beast` number, since 8 + 1 + 3 + 8 + 7 + 9 + 5 + 622 + 3 = 666.

It is not a de Polignac number, because 81387956223 - 2⁵ = 81387956191 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81387956223.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81387956203) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 79713453 + ... + 79714473.

It is an arithmetic number, because the mean of its divisors is an integer number (1126325760).

Almost surely, 2^81387956223 is an apocalyptic number.

81387956223 is a deficient number, since it is larger than the sum of its proper divisors (62781741057).

81387956223 is a wasteful number, since it uses less digits than its factorization.

81387956223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1217 (or 1199 counting only the distinct ones).

The product of its digits is 4354560, while the sum is 54.

The spelling of 81387956223 in words is "eighty-one billion, three hundred eighty-seven million, nine hundred fifty-six thousand, two hundred twenty-three".