6667443440 has 80 divisors (see below), whose sum is σ = 17744453568. Its totient is φ = 2282354688.

The previous prime is 6667443439. The next prime is 6667443449. The reversal of 6667443440 is 443447666.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a junction number, because it is equal to n+sod(n) for n = 6667443391 and 6667443400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6667443449) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 356564 + ... + 374796.

Almost surely, 2^6667443440 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6667443440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8872226784).

6667443440 is an abundant number, since it is smaller than the sum of its proper divisors (11077010128).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6667443440 is a wasteful number, since it uses less digits than its factorization.

6667443440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18906 (or 18900 counting only the distinct ones).

The product of its (nonzero) digits is 1161216, while the sum is 44.

The square root of 6667443440 is about 81654.4147000026. The cubic root of 6667443440 is about 1882.1451520925.

The spelling of 6667443440 in words is "six billion, six hundred sixty-seven million, four hundred forty-three thousand, four hundred forty".