81236273 has 2 divisors, whose sum is σ = 81236274. Its totient is φ = 81236272.

The previous prime is 81236249. The next prime is 81236303. The reversal of 81236273 is 37263218.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 81126049 + 110224 = 9007^2 + 332^2 .

It is a cyclic number.

It is not a de Polignac number, because 81236273 - 2¹⁰ = 81235249 is a prime.

It is not a weakly prime, because it can be changed into another prime (81236873) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40618136 + 40618137.

It is an arithmetic number, because the mean of its divisors is an integer number (40618137).

Almost surely, 2^81236273 is an apocalyptic number.

It is an amenable number.

81236273 is a deficient number, since it is larger than the sum of its proper divisors (1).

81236273 is an equidigital number, since it uses as much as digits as its factorization.

81236273 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12096, while the sum is 32.

The square root of 81236273 is about 9013.1167195371. The cubic root of 81236273 is about 433.0951597804.

The spelling of 81236273 in words is "eighty-one million, two hundred thirty-six thousand, two hundred seventy-three".