81236897 has 32 divisors (see below), whose sum is σ = 104343552. Its totient is φ = 61611264.

The previous prime is 81236891. The next prime is 81236927. The reversal of 81236897 is 79863218.

It is not a de Polignac number, because 81236897 - 2¹⁸ = 80974753 is a prime.

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (81236891) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 183158 + ... + 183600.

It is an arithmetic number, because the mean of its divisors is an integer number (3260736).

Almost surely, 2^81236897 is an apocalyptic number.

It is an amenable number.

81236897 is a deficient number, since it is larger than the sum of its proper divisors (23106655).

81236897 is a wasteful number, since it uses less digits than its factorization.

81236897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 557.

The product of its digits is 145152, while the sum is 44.

The square root of 81236897 is about 9013.1513356872. The cubic root of 81236897 is about 433.0962686885.

The spelling of 81236897 in words is "eighty-one million, two hundred thirty-six thousand, eight hundred ninety-seven".