81574016 has 16 divisors (see below), whose sum is σ = 162510990. Its totient is φ = 40786944.

The previous prime is 81573997. The next prime is 81574037. The reversal of 81574016 is 61047518.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 75620416 + 5953600 = 8696^2 + 2440^2 .

It is a tau number, because it is divible by the number of its divisors (16).

It is a Harshad number since it is a multiple of its sum of digits (32).

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 318521 + ... + 318776.

Almost surely, 2^81574016 is an apocalyptic number.

It is an amenable number.

81574016 is a deficient number, since it is larger than the sum of its proper divisors (80936974).

81574016 is an equidigital number, since it uses as much as digits as its factorization.

81574016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 637311 (or 637299 counting only the distinct ones).

The product of its (nonzero) digits is 6720, while the sum is 32.

The square root of 81574016 is about 9031.8334794216. The cubic root of 81574016 is about 433.6945332933.

The spelling of 81574016 in words is "eighty-one million, five hundred seventy-four thousand, sixteen".