6651661005 has 48 divisors (see below), whose sum is σ = 12997951680. Its totient is φ = 3225039840.

The previous prime is 6651660991. The next prime is 6651661061. The reversal of 6651661005 is 5001661566.

It is not a de Polignac number, because 6651661005 - 2⁴ = 6651660989 is a prime.

It is a super-2 number, since 2×6651661005² = 88489188250875220050, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 187267 + ... + 219936.

It is an arithmetic number, because the mean of its divisors is an integer number (270790660).

Almost surely, 2^6651661005 is an apocalyptic number.

It is an amenable number.

6651661005 is a deficient number, since it is larger than the sum of its proper divisors (6346290675).

6651661005 is a wasteful number, since it uses less digits than its factorization.

6651661005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 407239 (or 407222 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 36.

The square root of 6651661005 is about 81557.7157907209. The cubic root of 6651661005 is about 1880.6589101438.

The spelling of 6651661005 in words is "six billion, six hundred fifty-one million, six hundred sixty-one thousand, five".