6781351681 has 8 divisors (see below), whose sum is σ = 7323341760. Its totient is φ = 6242268432.

The previous prime is 6781351667. The next prime is 6781351723. The reversal of 6781351681 is 1861531876.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 6781351681 - 2⁷ = 6781351553 is a prime.

It is a super-2 number, since 2×6781351681² = 91973461242803051522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6781351631) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 721855 + ... + 731188.

It is an arithmetic number, because the mean of its divisors is an integer number (915417720).

Almost surely, 2^6781351681 is an apocalyptic number.

It is an amenable number.

6781351681 is a deficient number, since it is larger than the sum of its proper divisors (541990079).

6781351681 is a wasteful number, since it uses less digits than its factorization.

6781351681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1453415.

The product of its digits is 241920, while the sum is 46.

The square root of 6781351681 is about 82348.9628410704. The cubic root of 6781351681 is about 1892.8030299560.

The spelling of 6781351681 in words is "six billion, seven hundred eighty-one million, three hundred fifty-one thousand, six hundred eighty-one".