81171478 has 8 divisors (see below), whose sum is σ = 122963040. Its totient is φ = 40183800.

The previous prime is 81171469. The next prime is 81171499. The reversal of 81171478 is 87417118.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 200718 + ... + 201121.

It is an arithmetic number, because the mean of its divisors is an integer number (15370380).

Almost surely, 2^81171478 is an apocalyptic number.

81171478 is a deficient number, since it is larger than the sum of its proper divisors (41791562).

81171478 is a wasteful number, since it uses less digits than its factorization.

81171478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 401942.

The product of its digits is 12544, while the sum is 37.

The square root of 81171478 is about 9009.5215189265. The cubic root of 81171478 is about 432.9799819002.

The spelling of 81171478 in words is "eighty-one million, one hundred seventy-one thousand, four hundred seventy-eight".