1666667904 has 64 divisors (see below), whose sum is σ = 4829561280. Its totient is φ = 505049600.

The previous prime is 1666667869. The next prime is 1666667909. The reversal of 1666667904 is 4097666661.

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1666667909) 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, 193062 + ... + 201509.

It is an arithmetic number, because the mean of its divisors is an integer number (75461895).

Almost surely, 2^1666667904 is an apocalyptic number.

It is an amenable number.

1666667904 is an abundant number, since it is smaller than the sum of its proper divisors (3162893376).

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

1666667904 is a wasteful number, since it uses less digits than its factorization.

1666667904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 394599 (or 394587 counting only the distinct ones).

The product of its (nonzero) digits is 1959552, while the sum is 51.

The square root of 1666667904 is about 40824.8442005600. The cubic root of 1666667904 is about 1185.6313949008.

The spelling of 1666667904 in words is "one billion, six hundred sixty-six million, six hundred sixty-seven thousand, nine hundred four".