81336770 has 16 divisors (see below), whose sum is σ = 146511288. Its totient is φ = 32511360.

The previous prime is 81336733. The next prime is 81336803. The reversal of 81336770 is 7763318.

It can be written as a sum of positive squares in 4 ways, for example, as 61293241 + 20043529 = 7829^2 + 4477^2 .

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 81336770.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21200 + ... + 24740.

Almost surely, 2^81336770 is an apocalyptic number.

81336770 is a deficient number, since it is larger than the sum of its proper divisors (65174518).

81336770 is a wasteful number, since it uses less digits than its factorization.

81336770 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5845.

The product of its (nonzero) digits is 21168, while the sum is 35.

The square root of 81336770 is about 9018.6900379157. The cubic root of 81336770 is about 433.2736794937.

The spelling of 81336770 in words is "eighty-one million, three hundred thirty-six thousand, seven hundred seventy".