81544871219 has 8 divisors (see below), whose sum is σ = 96407729760. Its totient is φ = 67485410496.

The previous prime is 81544871207. The next prime is 81544871231. The reversal of 81544871219 is 91217844518.

It is an interprime number because it is at equal distance from previous prime (81544871207) and next prime (81544871231).

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

It is a de Polignac number, because none of the positive numbers 2^k-81544871219 is a prime.

It is a super-2 number, since 2×81544871219² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81544871249) 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, 200849234 + ... + 200849639.

It is an arithmetic number, because the mean of its divisors is an integer number (12050966220).

Almost surely, 2^81544871219 is an apocalyptic number.

81544871219 is a deficient number, since it is larger than the sum of its proper divisors (14862858541).

81544871219 is a wasteful number, since it uses less digits than its factorization.

81544871219 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 401698909.

The product of its digits is 645120, while the sum is 50.

The spelling of 81544871219 in words is "eighty-one billion, five hundred forty-four million, eight hundred seventy-one thousand, two hundred nineteen".