6721318 has 4 divisors (see below), whose sum is σ = 10081980. Its totient is φ = 3360658.

The previous prime is 6721303. The next prime is 6721331. The reversal of 6721318 is 8131276.

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

It is a super-2 number, since 2×6721318² = 90352231314248, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1680328 + ... + 1680331.

It is an arithmetic number, because the mean of its divisors is an integer number (2520495).

Almost surely, 2^6721318 is an apocalyptic number.

6721318 is a deficient number, since it is larger than the sum of its proper divisors (3360662).

6721318 is a wasteful number, since it uses less digits than its factorization.

6721318 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3360661.

The product of its digits is 2016, while the sum is 28.

The square root of 6721318 is about 2592.5504816686. The cubic root of 6721318 is about 188.7200955504.

It can be divided in two parts, 6721 and 318, that multiplied together give a triangular number (2137278 = T₂₀₆₇).

The spelling of 6721318 in words is "six million, seven hundred twenty-one thousand, three hundred eighteen".