81490571 has 8 divisors (see below), whose sum is σ = 87699744. Its totient is φ = 75438720.

The previous prime is 81490567. The next prime is 81490589. The reversal of 81490571 is 17509418.

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 81490571 - 2² = 81490567 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81490511) 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, 38255 + ... + 40328.

It is an arithmetic number, because the mean of its divisors is an integer number (10962468).

Almost surely, 2^81490571 is an apocalyptic number.

81490571 is a deficient number, since it is larger than the sum of its proper divisors (6209173).

81490571 is a wasteful number, since it uses less digits than its factorization.

81490571 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78661.

The product of its (nonzero) digits is 10080, while the sum is 35.

The square root of 81490571 is about 9027.2128035180. The cubic root of 81490571 is about 433.5466022526.

Adding to 81490571 its reverse (17509418), we get a palindrome (98999989).

The spelling of 81490571 in words is "eighty-one million, four hundred ninety thousand, five hundred seventy-one".