81770074 has 16 divisors (see below), whose sum is σ = 127704168. Its totient is φ = 39232512.

The previous prime is 81770071. The next prime is 81770081. The reversal of 81770074 is 47007718.

It can be written as a sum of positive squares in 4 ways, for example, as 81270225 + 499849 = 9015^2 + 707^2 .

It is not an unprimeable number, because it can be changed into a prime (81770071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2167 + ... + 12970.

Almost surely, 2^81770074 is an apocalyptic number.

81770074 is a deficient number, since it is larger than the sum of its proper divisors (45934094).

81770074 is a wasteful number, since it uses less digits than its factorization.

81770074 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15249.

The product of its (nonzero) digits is 10976, while the sum is 34.

The square root of 81770074 is about 9042.6806866106. The cubic root of 81770074 is about 434.0417077857.

The spelling of 81770074 in words is "eighty-one million, seven hundred seventy thousand, seventy-four".