81710501 has 2 divisors, whose sum is σ = 81710502. Its totient is φ = 81710500.

The previous prime is 81710441. The next prime is 81710527. The reversal of 81710501 is 10501718.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 76300225 + 5410276 = 8735^2 + 2326^2 .

It is a cyclic number.

It is not a de Polignac number, because 81710501 - 2⁶ = 81710437 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81710561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40855250 + 40855251.

It is an arithmetic number, because the mean of its divisors is an integer number (40855251).

Almost surely, 2^81710501 is an apocalyptic number.

It is an amenable number.

81710501 is a deficient number, since it is larger than the sum of its proper divisors (1).

81710501 is an equidigital number, since it uses as much as digits as its factorization.

81710501 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 280, while the sum is 23.

The square root of 81710501 is about 9039.3860964116. The cubic root of 81710501 is about 433.9362761883.

The spelling of 81710501 in words is "eighty-one million, seven hundred ten thousand, five hundred one".