6649666658 has 8 divisors (see below), whose sum is σ = 9983886528. Its totient is φ = 3321704484.

The previous prime is 6649666651. The next prime is 6649666693. The reversal of 6649666658 is 8566669466.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 6649666658.

It is not an unprimeable number, because it can be changed into a prime (6649666651) 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, 1561766 + ... + 1566017.

It is an arithmetic number, because the mean of its divisors is an integer number (1247985816).

Almost surely, 2^6649666658 is an apocalyptic number.

6649666658 is a deficient number, since it is larger than the sum of its proper divisors (3334219870).

6649666658 is a wasteful number, since it uses less digits than its factorization.

6649666658 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3128848.

The product of its digits is 67184640, while the sum is 62.

The square root of 6649666658 is about 81545.4882749500. The cubic root of 6649666658 is about 1880.4709339693.

The spelling of 6649666658 in words is "six billion, six hundred forty-nine million, six hundred sixty-six thousand, six hundred fifty-eight".