6781213 has 4 divisors (see below), whose sum is σ = 6797308. Its totient is φ = 6765120.

The previous prime is 6781193. The next prime is 6781223. The reversal of 6781213 is 3121876.

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

It can be written as a sum of positive squares in 2 ways, for example, as 4214809 + 2566404 = 2053^2 + 1602^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6781213 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6781223) 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, 7398 + ... + 8263.

It is an arithmetic number, because the mean of its divisors is an integer number (1699327).

Almost surely, 2^6781213 is an apocalyptic number.

It is an amenable number.

6781213 is a deficient number, since it is larger than the sum of its proper divisors (16095).

6781213 is a wasteful number, since it uses less digits than its factorization.

6781213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16094.

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

The square root of 6781213 is about 2604.0762277629. The cubic root of 6781213 is about 189.2790127041.

It can be divided in two parts, 678 and 1213, that added together give a triangular number (1891 = T₆₁).

The spelling of 6781213 in words is "six million, seven hundred eighty-one thousand, two hundred thirteen".