1668403688 has 16 divisors (see below), whose sum is σ = 3575150880. Its totient is φ = 715030128.

The previous prime is 1668403687. The next prime is 1668403703. The reversal of 1668403688 is 8863048661.

It is a happy number.

It is a super-2 number, since 2×1668403688² = 5567141732264002688, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1668403687) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14896406 + ... + 14896517.

It is an arithmetic number, because the mean of its divisors is an integer number (223446930).

Almost surely, 2^1668403688 is an apocalyptic number.

It is an amenable number.

1668403688 is an abundant number, since it is smaller than the sum of its proper divisors (1906747192).

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

1668403688 is a wasteful number, since it uses less digits than its factorization.

1668403688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29792936 (or 29792932 counting only the distinct ones).

The product of its (nonzero) digits is 1327104, while the sum is 50.

The square root of 1668403688 is about 40846.0975859384. The cubic root of 1668403688 is about 1186.0428517893.

The spelling of 1668403688 in words is "one billion, six hundred sixty-eight million, four hundred three thousand, six hundred eighty-eight".