81445316 has 12 divisors (see below), whose sum is σ = 143254188. Its totient is φ = 40515552.

The previous prime is 81445279. The next prime is 81445349. The reversal of 81445316 is 61354418.

81445316 = T₂₀₁ + T₂₀₂ + ... + T₇₉₁.

It can be written as a sum of positive squares in 2 ways, for example, as 74891716 + 6553600 = 8654^2 + 2560^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 50891 + ... + 52466.

It is an arithmetic number, because the mean of its divisors is an integer number (11937849).

Almost surely, 2^81445316 is an apocalyptic number.

It is an amenable number.

81445316 is a deficient number, since it is larger than the sum of its proper divisors (61808872).

81445316 is a wasteful number, since it uses less digits than its factorization.

81445316 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103558 (or 103556 counting only the distinct ones).

The product of its digits is 11520, while the sum is 32.

The square root of 81445316 is about 9024.7058677832. The cubic root of 81445316 is about 433.4663320884.

The spelling of 81445316 in words is "eighty-one million, four hundred forty-five thousand, three hundred sixteen".