81038723 has 2 divisors, whose sum is σ = 81038724. Its totient is φ = 81038722.

The previous prime is 81038717. The next prime is 81038767. The reversal of 81038723 is 32783018.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81038723 - 2⁸ = 81038467 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a self number, because there is not a number n which added to its sum of digits gives 81038723.

It is not a weakly prime, because it can be changed into another prime (81031723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40519361 + 40519362.

It is an arithmetic number, because the mean of its divisors is an integer number (40519362).

Almost surely, 2^81038723 is an apocalyptic number.

81038723 is a deficient number, since it is larger than the sum of its proper divisors (1).

81038723 is an equidigital number, since it uses as much as digits as its factorization.

81038723 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8064, while the sum is 32.

The square root of 81038723 is about 9002.1510207283. The cubic root of 81038723 is about 432.7438085402.

The spelling of 81038723 in words is "eighty-one million, thirty-eight thousand, seven hundred twenty-three".