667728478444 has 12 divisors (see below), whose sum is σ = 1168573951944. Its totient is φ = 333850206464.

The previous prime is 667728478433. The next prime is 667728478499. The reversal of 667728478444 is 444874827766.

667728478444 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×667728478444² (a number of 24 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 667728478444.

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, 3400762 + ... + 3591745.

It is an arithmetic number, because the mean of its divisors is an integer number (97381162662).

Almost surely, 2^667728478444 is an apocalyptic number.

It is an amenable number.

667728478444 is a deficient number, since it is larger than the sum of its proper divisors (500845473500).

667728478444 is a wasteful number, since it uses less digits than its factorization.

667728478444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7016384 (or 7016382 counting only the distinct ones).

The product of its digits is 404619264, while the sum is 67.

The spelling of 667728478444 in words is "six hundred sixty-seven billion, seven hundred twenty-eight million, four hundred seventy-eight thousand, four hundred forty-four".