81130774 has 4 divisors (see below), whose sum is σ = 121696164. Its totient is φ = 40565386.

The previous prime is 81130739. The next prime is 81130781. The reversal of 81130774 is 47703118.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20282692 + ... + 20282695.

It is an arithmetic number, because the mean of its divisors is an integer number (30424041).

Almost surely, 2^81130774 is an apocalyptic number.

81130774 is a deficient number, since it is larger than the sum of its proper divisors (40565390).

81130774 is a wasteful number, since it uses less digits than its factorization.

81130774 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40565389.

The product of its (nonzero) digits is 4704, while the sum is 31.

The square root of 81130774 is about 9007.2622921729. The cubic root of 81130774 is about 432.9075961956.

The spelling of 81130774 in words is "eighty-one million, one hundred thirty thousand, seven hundred seventy-four".