81275019 has 8 divisors (see below), whose sum is σ = 123847680. Its totient is φ = 46442856.

The previous prime is 81275017. The next prime is 81275069. The reversal of 81275019 is 91057218.

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

It is not a de Polignac number, because 81275019 - 2¹ = 81275017 is a prime.

It is a super-4 number, since 4×81275019⁴ (a number of 33 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (81275017) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1935099 + ... + 1935140.

It is an arithmetic number, because the mean of its divisors is an integer number (15480960).

Almost surely, 2^81275019 is an apocalyptic number.

81275019 is a deficient number, since it is larger than the sum of its proper divisors (42572661).

81275019 is a wasteful number, since it uses less digits than its factorization.

81275019 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3870249.

The product of its (nonzero) digits is 5040, while the sum is 33.

The square root of 81275019 is about 9015.2658862620. The cubic root of 81275019 is about 433.1640043875.

The spelling of 81275019 in words is "eighty-one million, two hundred seventy-five thousand, nineteen".