81244219 has 8 divisors (see below), whose sum is σ = 93032928. Its totient is φ = 69501120.

The previous prime is 81244201. The next prime is 81244259. The reversal of 81244219 is 91244218.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81244219 - 2²¹ = 79147067 is a prime.

It is a super-2 number, since 2×81244219² = 13201246241839922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81244259) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7492 + ... + 14785.

It is an arithmetic number, because the mean of its divisors is an integer number (11629116).

Almost surely, 2^81244219 is an apocalyptic number.

81244219 is a deficient number, since it is larger than the sum of its proper divisors (11788709).

81244219 is a wasteful number, since it uses less digits than its factorization.

81244219 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22805.

The product of its digits is 4608, while the sum is 31.

The square root of 81244219 is about 9013.5575107723. The cubic root of 81244219 is about 433.1092801637.

Subtracting 81244219 from its reverse (91244218), we obtain a palindrome (9999999).

The spelling of 81244219 in words is "eighty-one million, two hundred forty-four thousand, two hundred nineteen".