81074539 has 24 divisors (see below), whose sum is σ = 105642240. Its totient is φ = 60753888.

The previous prime is 81074537. The next prime is 81074557. The reversal of 81074539 is 93547018.

It is not a de Polignac number, because 81074539 - 2¹ = 81074537 is a prime.

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81074498 and 81074507.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81074533) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 20674 + ... + 24280.

It is an arithmetic number, because the mean of its divisors is an integer number (4401760).

Almost surely, 2^81074539 is an apocalyptic number.

81074539 is a deficient number, since it is larger than the sum of its proper divisors (24567701).

81074539 is a wasteful number, since it uses less digits than its factorization.

81074539 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3659 (or 3646 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 37.

The square root of 81074539 is about 9004.1401033080. The cubic root of 81074539 is about 432.8075511926.

The spelling of 81074539 in words is "eighty-one million, seventy-four thousand, five hundred thirty-nine".