81048817 has 4 divisors (see below), whose sum is σ = 81396900. Its totient is φ = 80700736.

The previous prime is 81048811. The next prime is 81048827. The reversal of 81048817 is 71884018.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 71884018 = 2 ⋅35942009.

It can be written as a sum of positive squares in 2 ways, for example, as 44675856 + 36372961 = 6684^2 + 6031^2 .

It is a cyclic number.

It is not a de Polignac number, because 81048817 - 2²³ = 72660209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81048811) 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, 173692 + ... + 174157.

It is an arithmetic number, because the mean of its divisors is an integer number (20349225).

Almost surely, 2^81048817 is an apocalyptic number.

It is an amenable number.

81048817 is a deficient number, since it is larger than the sum of its proper divisors (348083).

81048817 is a wasteful number, since it uses less digits than its factorization.

81048817 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 348082.

The product of its (nonzero) digits is 14336, while the sum is 37.

The square root of 81048817 is about 9002.7116470539. The cubic root of 81048817 is about 432.7617749908.

The spelling of 81048817 in words is "eighty-one million, forty-eight thousand, eight hundred seventeen".