81452219 has 4 divisors (see below), whose sum is σ = 86243544. Its totient is φ = 76660896.

The previous prime is 81452201. The next prime is 81452233. The reversal of 81452219 is 91225418.

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

It is a cyclic number.

It is not a de Polignac number, because 81452219 - 2⁸ = 81451963 is a prime.

It is a super-2 number, since 2×81452219² = 13268927960047922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81452249) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2395637 + ... + 2395670.

It is an arithmetic number, because the mean of its divisors is an integer number (21560886).

Almost surely, 2^81452219 is an apocalyptic number.

81452219 is a deficient number, since it is larger than the sum of its proper divisors (4791325).

81452219 is a wasteful number, since it uses less digits than its factorization.

81452219 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4791324.

The product of its digits is 5760, while the sum is 32.

The square root of 81452219 is about 9025.0883098173. The cubic root of 81452219 is about 433.4785780701.

The spelling of 81452219 in words is "eighty-one million, four hundred fifty-two thousand, two hundred nineteen".