81436328 has 8 divisors (see below), whose sum is σ = 152693130. Its totient is φ = 40718160.

The previous prime is 81436319. The next prime is 81436393. The reversal of 81436328 is 82363418.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 69588964 + 11847364 = 8342^2 + 3442^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5089763 + ... + 5089778.

Almost surely, 2^81436328 is an apocalyptic number.

It is an amenable number.

81436328 is a deficient number, since it is larger than the sum of its proper divisors (71256802).

81436328 is a wasteful number, since it uses less digits than its factorization.

81436328 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10179547 (or 10179543 counting only the distinct ones).

The product of its digits is 27648, while the sum is 35.

The square root of 81436328 is about 9024.2078876763. The cubic root of 81436328 is about 433.4503862615.

The spelling of 81436328 in words is "eighty-one million, four hundred thirty-six thousand, three hundred twenty-eight".