16668433509 has 16 divisors (see below), whose sum is σ = 27353327232. Its totient is φ = 8792140608.

The previous prime is 16668433471. The next prime is 16668433517. The reversal of 16668433509 is 90533486661.

It is a happy number.

It is not a de Polignac number, because 16668433509 - 2⁷ = 16668433381 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16668433009) 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, 30527994 + ... + 30528539.

It is an arithmetic number, because the mean of its divisors is an integer number (1709582952).

Almost surely, 2^16668433509 is an apocalyptic number.

It is an amenable number.

16668433509 is a deficient number, since it is larger than the sum of its proper divisors (10684893723).

16668433509 is a wasteful number, since it uses less digits than its factorization.

16668433509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61056556.

The product of its (nonzero) digits is 2799360, while the sum is 51.

The spelling of 16668433509 in words is "sixteen billion, six hundred sixty-eight million, four hundred thirty-three thousand, five hundred nine".