6651138989 has 16 divisors (see below), whose sum is σ = 7379109504. Its totient is φ = 5944262400.

The previous prime is 6651138983. The next prime is 6651139003. The reversal of 6651138989 is 9898311566.

It is a cyclic number.

It is not a de Polignac number, because 6651138989 - 2⁸ = 6651138733 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6651138983) 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, 236417 + ... + 263049.

It is an arithmetic number, because the mean of its divisors is an integer number (461194344).

Almost surely, 2^6651138989 is an apocalyptic number.

It is an amenable number.

6651138989 is a deficient number, since it is larger than the sum of its proper divisors (727970515).

6651138989 is a wasteful number, since it uses less digits than its factorization.

6651138989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27028.

The product of its digits is 2799360, while the sum is 56.

The square root of 6651138989 is about 81554.5154421262. The cubic root of 6651138989 is about 1880.6097114187.

The spelling of 6651138989 in words is "six billion, six hundred fifty-one million, one hundred thirty-eight thousand, nine hundred eighty-nine".