6643954 has 4 divisors (see below), whose sum is σ = 9965934. Its totient is φ = 3321976.

The previous prime is 6643919. The next prime is 6643969. The reversal of 6643954 is 4593466.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 4593466 = 2 ⋅2296733.

It can be written as a sum of positive squares in only one way, i.e., 6640929 + 3025 = 2577^2 + 55^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1660987 + ... + 1660990.

Almost surely, 2^6643954 is an apocalyptic number.

6643954 is a deficient number, since it is larger than the sum of its proper divisors (3321980).

6643954 is a wasteful number, since it uses less digits than its factorization.

6643954 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3321979.

The product of its digits is 77760, while the sum is 37.

The square root of 6643954 is about 2577.5868559566. The cubic root of 6643954 is about 187.9932282154.

The spelling of 6643954 in words is "six million, six hundred forty-three thousand, nine hundred fifty-four".