665678438546 has 16 divisors (see below), whose sum is σ = 1089873633888. Its totient is φ = 302419540800.

The previous prime is 665678438543. The next prime is 665678438609. The reversal of 665678438546 is 645834876566.

665678438546 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (665678438543) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8036240 + ... + 8118651.

It is an arithmetic number, because the mean of its divisors is an integer number (68117102118).

Almost surely, 2^665678438546 is an apocalyptic number.

665678438546 is a deficient number, since it is larger than the sum of its proper divisors (424195195342).

665678438546 is a wasteful number, since it uses less digits than its factorization.

665678438546 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16156777.

The product of its digits is 696729600, while the sum is 68.

The spelling of 665678438546 in words is "six hundred sixty-five billion, six hundred seventy-eight million, four hundred thirty-eight thousand, five hundred forty-six".