81144395 has 4 divisors (see below), whose sum is σ = 97373280. Its totient is φ = 64915512.

The previous prime is 81144389. The next prime is 81144403. The reversal of 81144395 is 59344118.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81144395 - 2¹⁶ = 81078859 is a prime.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 8114435 + ... + 8114444.

It is an arithmetic number, because the mean of its divisors is an integer number (24343320).

Almost surely, 2^81144395 is an apocalyptic number.

81144395 is a deficient number, since it is larger than the sum of its proper divisors (16228885).

81144395 is a wasteful number, since it uses less digits than its factorization.

81144395 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16228884.

The product of its digits is 17280, while the sum is 35.

The square root of 81144395 is about 9008.0183725390. The cubic root of 81144395 is about 432.9318217108.

The spelling of 81144395 in words is "eighty-one million, one hundred forty-four thousand, three hundred ninety-five".