81641438127 has 12 divisors (see below), whose sum is σ = 117970024224. Its totient is φ = 54407547360.

The previous prime is 81641438111. The next prime is 81641438147. The reversal of 81641438127 is 72183414618.

81641438127 is a `hidden beast` number, since 81 + 6 + 414 + 38 + 127 = 666.

It is not a de Polignac number, because 81641438127 - 2⁴ = 81641438111 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81641438107) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1647399 + ... + 1696232.

It is an arithmetic number, because the mean of its divisors is an integer number (9830835352).

Almost surely, 2^81641438127 is an apocalyptic number.

81641438127 is a deficient number, since it is larger than the sum of its proper divisors (36328586097).

81641438127 is a wasteful number, since it uses less digits than its factorization.

81641438127 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3346350 (or 3346347 counting only the distinct ones).

The product of its digits is 258048, while the sum is 45.

The spelling of 81641438127 in words is "eighty-one billion, six hundred forty-one million, four hundred thirty-eight thousand, one hundred twenty-seven".