6721131 has 4 divisors (see below), whose sum is σ = 8961512. Its totient is φ = 4480752.

The previous prime is 6721123. The next prime is 6721133. The reversal of 6721131 is 1311276.

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

It is not a de Polignac number, because 6721131 - 2³ = 6721123 is a prime.

It is a super-2 number, since 2×6721131² = 90347203838322, which contains 22 as substring.

It is a D-number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6721098 and 6721107.

It is not an unprimeable number, because it can be changed into a prime (6721133) by changing a digit.

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, 1120186 + ... + 1120191.

It is an arithmetic number, because the mean of its divisors is an integer number (2240378).

Almost surely, 2^6721131 is an apocalyptic number.

6721131 is a deficient number, since it is larger than the sum of its proper divisors (2240381).

6721131 is a wasteful number, since it uses less digits than its factorization.

6721131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2240380.

The product of its digits is 252, while the sum is 21.

The square root of 6721131 is about 2592.5144165462. The cubic root of 6721131 is about 188.7183453487.

The spelling of 6721131 in words is "six million, seven hundred twenty-one thousand, one hundred thirty-one".