81124386071 has 4 divisors (see below), whose sum is σ = 81124955832. Its totient is φ = 81123816312.

The previous prime is 81124386061. The next prime is 81124386137. The reversal of 81124386071 is 17068342118.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 17068342118 = 2 ⋅8534171059.

It is a cyclic number.

It is not a de Polignac number, because 81124386071 - 2¹⁴ = 81124369687 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81124386041) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 133925 + ... + 424481.

It is an arithmetic number, because the mean of its divisors is an integer number (20281238958).

Almost surely, 2^81124386071 is an apocalyptic number.

81124386071 is a deficient number, since it is larger than the sum of its proper divisors (569761).

81124386071 is a wasteful number, since it uses less digits than its factorization.

81124386071 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 569760.

The product of its (nonzero) digits is 64512, while the sum is 41.

The spelling of 81124386071 in words is "eighty-one billion, one hundred twenty-four million, three hundred eighty-six thousand, seventy-one".