6621005 has 4 divisors (see below), whose sum is σ = 7945212. Its totient is φ = 5296800.

The previous prime is 6620981. The next prime is 6621029. The reversal of 6621005 is 5001266.

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

It is an interprime number because it is at equal distance from previous prime (6620981) and next prime (6621029).

It can be written as a sum of positive squares in 2 ways, for example, as 2319529 + 4301476 = 1523^2 + 2074^2 .

It is not a de Polignac number, because 6621005 - 2¹⁰ = 6619981 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

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 in 3 ways as a sum of consecutive naturals, for example, 662096 + ... + 662105.

It is an arithmetic number, because the mean of its divisors is an integer number (1986303).

Almost surely, 2^6621005 is an apocalyptic number.

It is an amenable number.

6621005 is a deficient number, since it is larger than the sum of its proper divisors (1324207).

6621005 is a wasteful number, since it uses less digits than its factorization.

6621005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1324206.

The product of its (nonzero) digits is 360, while the sum is 20.

The square root of 6621005 is about 2573.1313608131. The cubic root of 6621005 is about 187.7765282671.

The spelling of 6621005 in words is "six million, six hundred twenty-one thousand, five".