81332019 has 20 divisors (see below), whose sum is σ = 121999944. Its totient is φ = 53996544.

The previous prime is 81332011. The next prime is 81332021. The reversal of 81332019 is 91023318.

It is not a de Polignac number, because 81332019 - 2³ = 81332011 is a prime.

It is a super-2 number, since 2×81332019² = 13229794629232722, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 81331983 and 81332001.

It is not an unprimeable number, because it can be changed into a prime (81332011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 18864 + ... + 22770.

Almost surely, 2^81332019 is an apocalyptic number.

81332019 is a deficient number, since it is larger than the sum of its proper divisors (40667925).

81332019 is a wasteful number, since it uses less digits than its factorization.

81332019 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4176 (or 4167 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 81332019 is about 9018.4266366146. The cubic root of 81332019 is about 433.2652432792.

The spelling of 81332019 in words is "eighty-one million, three hundred thirty-two thousand, nineteen".