81027297 has 20 divisors (see below), whose sum is σ = 130353300. Its totient is φ = 49862304.

The previous prime is 81027293. The next prime is 81027313. The reversal of 81027297 is 79272018.

It can be written as a sum of positive squares in 2 ways, for example, as 32251041 + 48776256 = 5679^2 + 6984^2 .

It is not a de Polignac number, because 81027297 - 2² = 81027293 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81027293) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 37422 + ... + 39527.

It is an arithmetic number, because the mean of its divisors is an integer number (6517665).

Almost surely, 2^81027297 is an apocalyptic number.

It is an amenable number.

81027297 is a deficient number, since it is larger than the sum of its proper divisors (49326003).

81027297 is a wasteful number, since it uses less digits than its factorization.

81027297 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76974 (or 76965 counting only the distinct ones).

The product of its (nonzero) digits is 14112, while the sum is 36.

The square root of 81027297 is about 9001.5163722564. The cubic root of 81027297 is about 432.7234694439.

The spelling of 81027297 in words is "eighty-one million, twenty-seven thousand, two hundred ninety-seven".