6649971 has 4 divisors (see below), whose sum is σ = 8866632. Its totient is φ = 4433312.

The previous prime is 6649919. The next prime is 6649999. The reversal of 6649971 is 1799466.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 6649971 - 2¹¹ = 6647923 is a prime.

It is a super-2 number, since 2×6649971² = 88444228601682, which contains 22 as substring.

It is a D-number.

It is not an unprimeable number, because it can be changed into a prime (6649901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1108326 + ... + 1108331.

It is an arithmetic number, because the mean of its divisors is an integer number (2216658).

Almost surely, 2^6649971 is an apocalyptic number.

6649971 is a deficient number, since it is larger than the sum of its proper divisors (2216661).

6649971 is a wasteful number, since it uses less digits than its factorization.

6649971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2216660.

The product of its digits is 81648, while the sum is 42.

The square root of 6649971 is about 2578.7537687806. The cubic root of 6649971 is about 188.0499622002.

The spelling of 6649971 in words is "six million, six hundred forty-nine thousand, nine hundred seventy-one".