81119739 has 4 divisors (see below), whose sum is σ = 108159656. Its totient is φ = 54079824.

The previous prime is 81119719. The next prime is 81119741. The reversal of 81119739 is 93791118.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 81119739 - 2⁷ = 81119611 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81119697 and 81119706.

It is not an unprimeable number, because it can be changed into a prime (81119719) by changing a digit.

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 in 3 ways as a sum of consecutive naturals, for example, 13519954 + ... + 13519959.

It is an arithmetic number, because the mean of its divisors is an integer number (27039914).

Almost surely, 2^81119739 is an apocalyptic number.

81119739 is a deficient number, since it is larger than the sum of its proper divisors (27039917).

81119739 is a wasteful number, since it uses less digits than its factorization.

81119739 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27039916.

The product of its digits is 13608, while the sum is 39.

The square root of 81119739 is about 9006.6497100753. The cubic root of 81119739 is about 432.8879680007.

The spelling of 81119739 in words is "eighty-one million, one hundred nineteen thousand, seven hundred thirty-nine".