81371019 has 8 divisors (see below), whose sum is σ = 111141072. Its totient is φ = 52924160.

The previous prime is 81370997. The next prime is 81371021. The reversal of 81371019 is 91017318.

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 81371019 - 2⁹ = 81370507 is a prime.

It is a super-2 number, since 2×81371019² = 13242485466196722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81371219) 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, 330654 + ... + 330899.

It is an arithmetic number, because the mean of its divisors is an integer number (13892634).

Almost surely, 2^81371019 is an apocalyptic number.

81371019 is a deficient number, since it is larger than the sum of its proper divisors (29770053).

81371019 is a wasteful number, since it uses less digits than its factorization.

81371019 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 661597.

The product of its (nonzero) digits is 1512, while the sum is 30.

The square root of 81371019 is about 9020.5886171580. The cubic root of 81371019 is about 433.3344847438.

The spelling of 81371019 in words is "eighty-one million, three hundred seventy-one thousand, nineteen".