81125429839 has 8 divisors (see below), whose sum is σ = 81628031520. Its totient is φ = 80623028736.

The previous prime is 81125429813. The next prime is 81125429849. The reversal of 81125429839 is 93892452118.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81125429839 - 2⁷ = 81125429711 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 (81125429849) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 806367 + ... + 901375.

It is an arithmetic number, because the mean of its divisors is an integer number (10203503940).

Almost surely, 2^81125429839 is an apocalyptic number.

81125429839 is a deficient number, since it is larger than the sum of its proper divisors (502601681).

81125429839 is a wasteful number, since it uses less digits than its factorization.

81125429839 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100289.

The product of its digits is 1244160, while the sum is 52.

The spelling of 81125429839 in words is "eighty-one billion, one hundred twenty-five million, four hundred twenty-nine thousand, eight hundred thirty-nine".