1666694016 has 128 divisors (see below), whose sum is σ = 5297594400. Its totient is φ = 512815104.

The previous prime is 1666693999. The next prime is 1666694017. The reversal of 1666694016 is 6104966661.

1666694016 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1666694017) 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, 26380 + ... + 63476.

Almost surely, 2^1666694016 is an apocalyptic number.

1666694016 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1666694016, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2648797200).

1666694016 is an abundant number, since it is smaller than the sum of its proper divisors (3630900384).

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

1666694016 is a wasteful number, since it uses less digits than its factorization.

1666694016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37133 (or 37115 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 45.

The square root of 1666694016 is about 40825.1640045695. The cubic root of 1666694016 is about 1185.6375867053.

The spelling of 1666694016 in words is "one billion, six hundred sixty-six million, six hundred ninety-four thousand, sixteen".