6721355 has 4 divisors (see below), whose sum is σ = 8065632. Its totient is φ = 5377080.

The previous prime is 6721343. The next prime is 6721361. The reversal of 6721355 is 5531276.

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

It is not a de Polignac number, because 6721355 - 2¹⁰ = 6720331 is a prime.

It is a super-2 number, since 2×6721355² = 90353226072050, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

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, 672131 + ... + 672140.

It is an arithmetic number, because the mean of its divisors is an integer number (2016408).

Almost surely, 2^6721355 is an apocalyptic number.

6721355 is a deficient number, since it is larger than the sum of its proper divisors (1344277).

6721355 is a wasteful number, since it uses less digits than its factorization.

6721355 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1344276.

The product of its digits is 6300, while the sum is 29.

The square root of 6721355 is about 2592.5576174890. The cubic root of 6721355 is about 188.7204418431.

The spelling of 6721355 in words is "six million, seven hundred twenty-one thousand, three hundred fifty-five".