6721871 has 4 divisors (see below), whose sum is σ = 7238952. Its totient is φ = 6204792.

The previous prime is 6721867. The next prime is 6721879. The reversal of 6721871 is 1781276.

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 6721871 - 2² = 6721867 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6721879) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 258521 + ... + 258546.

It is an arithmetic number, because the mean of its divisors is an integer number (1809738).

Almost surely, 2^6721871 is an apocalyptic number.

6721871 is a deficient number, since it is larger than the sum of its proper divisors (517081).

6721871 is a wasteful number, since it uses less digits than its factorization.

6721871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 517080.

The product of its digits is 4704, while the sum is 32.

The square root of 6721871 is about 2592.6571312073. The cubic root of 6721871 is about 188.7252710904.

The spelling of 6721871 in words is "six million, seven hundred twenty-one thousand, eight hundred seventy-one".