81319574 has 8 divisors (see below), whose sum is σ = 139405008. Its totient is φ = 34851240.

The previous prime is 81319531. The next prime is 81319577. The reversal of 81319574 is 47591318.

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

It is a super-2 number, since 2×81319574² = 13225746231082952, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81319577) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2904257 + ... + 2904284.

It is an arithmetic number, because the mean of its divisors is an integer number (17425626).

Almost surely, 2^81319574 is an apocalyptic number.

81319574 is a deficient number, since it is larger than the sum of its proper divisors (58085434).

81319574 is a wasteful number, since it uses less digits than its factorization.

81319574 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5808550.

The product of its digits is 30240, while the sum is 38.

The square root of 81319574 is about 9017.7366339897. The cubic root of 81319574 is about 433.2431434917.

The spelling of 81319574 in words is "eighty-one million, three hundred nineteen thousand, five hundred seventy-four".