81044897 has 4 divisors (see below), whose sum is σ = 82574100. Its totient is φ = 79515696.

The previous prime is 81044863. The next prime is 81044927. The reversal of 81044897 is 79844018.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 59737441 + 21307456 = 7729^2 + 4616^2 .

It is a cyclic number.

It is not a de Polignac number, because 81044897 - 2⁶ = 81044833 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81044827) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 764522 + ... + 764627.

It is an arithmetic number, because the mean of its divisors is an integer number (20643525).

Almost surely, 2^81044897 is an apocalyptic number.

It is an amenable number.

81044897 is a deficient number, since it is larger than the sum of its proper divisors (1529203).

81044897 is a wasteful number, since it uses less digits than its factorization.

81044897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1529202.

The product of its (nonzero) digits is 64512, while the sum is 41.

The square root of 81044897 is about 9002.4939322390. The cubic root of 81044897 is about 432.7547979056.

The spelling of 81044897 in words is "eighty-one million, forty-four thousand, eight hundred ninety-seven".