6451861 has 4 divisors (see below), whose sum is σ = 6948172. Its totient is φ = 5955552.

The previous prime is 6451859. The next prime is 6451871. The reversal of 6451861 is 1681546.

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 3496900 + 2954961 = 1870^2 + 1719^2 .

It is a cyclic number.

It is not a de Polignac number, because 6451861 - 2¹ = 6451859 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 (6451871) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 248136 + ... + 248161.

It is an arithmetic number, because the mean of its divisors is an integer number (1737043).

Almost surely, 2^6451861 is an apocalyptic number.

It is an amenable number.

6451861 is a deficient number, since it is larger than the sum of its proper divisors (496311).

6451861 is a wasteful number, since it uses less digits than its factorization.

6451861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 496310.

The product of its digits is 5760, while the sum is 31.

The square root of 6451861 is about 2540.0513774331. The cubic root of 6451861 is about 186.1636994893.

The spelling of 6451861 in words is "six million, four hundred fifty-one thousand, eight hundred sixty-one".