6781601 has 4 divisors (see below), whose sum is σ = 6787092. Its totient is φ = 6776112.

The previous prime is 6781559. The next prime is 6781603. The reversal of 6781601 is 1061876.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 1380625 + 5400976 = 1175^2 + 2324^2 .

It is a cyclic number.

It is not a de Polignac number, because 6781601 - 2¹⁴ = 6765217 is a prime.

It is a super-2 number, since 2×6781601² = 91980224246402, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6781603) 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, 71 + ... + 3683.

It is an arithmetic number, because the mean of its divisors is an integer number (1696773).

Almost surely, 2^6781601 is an apocalyptic number.

It is an amenable number.

6781601 is a deficient number, since it is larger than the sum of its proper divisors (5491).

6781601 is a wasteful number, since it uses less digits than its factorization.

6781601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5490.

The product of its (nonzero) digits is 2016, while the sum is 29.

The square root of 6781601 is about 2604.1507252845. The cubic root of 6781601 is about 189.2826226215.

The spelling of 6781601 in words is "six million, seven hundred eighty-one thousand, six hundred one".