6851861 has 4 divisors (see below), whose sum is σ = 7149792. Its totient is φ = 6553932.

The previous prime is 6851839. The next prime is 6851863. The reversal of 6851861 is 1681586.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 6851861 - 2¹⁸ = 6589717 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 (6851863) 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, 148931 + ... + 148976.

It is an arithmetic number, because the mean of its divisors is an integer number (1787448).

Almost surely, 2^6851861 is an apocalyptic number.

It is an amenable number.

6851861 is a deficient number, since it is larger than the sum of its proper divisors (297931).

6851861 is a wasteful number, since it uses less digits than its factorization.

6851861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 297930.

The product of its digits is 11520, while the sum is 35.

The square root of 6851861 is about 2617.6059672915. The cubic root of 6851861 is about 189.9340583726.

The spelling of 6851861 in words is "six million, eight hundred fifty-one thousand, eight hundred sixty-one".