81896740 has 12 divisors (see below), whose sum is σ = 171983196. Its totient is φ = 32758688.

The previous prime is 81896687. The next prime is 81896741. The reversal of 81896740 is 4769818.

It can be written as a sum of positive squares in 2 ways, for example, as 11235904 + 70660836 = 3352^2 + 8406^2 .

It is not an unprimeable number, because it can be changed into a prime (81896741) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2047399 + ... + 2047438.

It is an arithmetic number, because the mean of its divisors is an integer number (14331933).

Almost surely, 2^81896740 is an apocalyptic number.

It is an amenable number.

81896740 is an abundant number, since it is smaller than the sum of its proper divisors (90086456).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81896740 is a wasteful number, since it uses less digits than its factorization.

81896740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4094846 (or 4094844 counting only the distinct ones).

The product of its (nonzero) digits is 96768, while the sum is 43.

The square root of 81896740 is about 9049.6817623605. The cubic root of 81896740 is about 434.2657097162.

The spelling of 81896740 in words is "eighty-one million, eight hundred ninety-six thousand, seven hundred forty".