6981781 has 8 divisors (see below), whose sum is σ = 7565184. Its totient is φ = 6417600.

The previous prime is 6981757. The next prime is 6981791. The reversal of 6981781 is 1871896.

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 6981781 - 2⁵ = 6981749 is a prime.

It is a super-2 number, since 2×6981781² = 97490531863922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6981731) 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, 4045 + ... + 5506.

It is an arithmetic number, because the mean of its divisors is an integer number (945648).

Almost surely, 2^6981781 is an apocalyptic number.

It is an amenable number.

6981781 is a deficient number, since it is larger than the sum of its proper divisors (583403).

6981781 is a wasteful number, since it uses less digits than its factorization.

6981781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9611.

The product of its digits is 24192, while the sum is 40.

The square root of 6981781 is about 2642.3060004473. The cubic root of 6981781 is about 191.1270136422.

The spelling of 6981781 in words is "six million, nine hundred eighty-one thousand, seven hundred eighty-one".