81124738472 has 8 divisors (see below), whose sum is σ = 152108884650. Its totient is φ = 40562369232.

The previous prime is 81124738469. The next prime is 81124738493. The reversal of 81124738472 is 27483742118.

It can be written as a sum of positive squares in only one way, i.e., 78856502596 + 2268235876 = 280814^2 + 47626^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5070296147 + ... + 5070296162.

Almost surely, 2^81124738472 is an apocalyptic number.

It is an amenable number.

81124738472 is a deficient number, since it is larger than the sum of its proper divisors (70984146178).

81124738472 is a wasteful number, since it uses less digits than its factorization.

81124738472 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10140592315 (or 10140592311 counting only the distinct ones).

The product of its digits is 602112, while the sum is 47.

The spelling of 81124738472 in words is "eighty-one billion, one hundred twenty-four million, seven hundred thirty-eight thousand, four hundred seventy-two".