6481781 has 8 divisors (see below), whose sum is σ = 6658560. Its totient is φ = 6307488.

The previous prime is 6481763. The next prime is 6481789. The reversal of 6481781 is 1871846.

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 6481781 - 2²² = 2287477 is a prime.

It is a super-2 number, since 2×6481781² = 84026969863922, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6481789) 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, 5420 + ... + 6506.

It is an arithmetic number, because the mean of its divisors is an integer number (832320).

Almost surely, 2^6481781 is an apocalyptic number.

It is an amenable number.

6481781 is a deficient number, since it is larger than the sum of its proper divisors (176779).

6481781 is a wasteful number, since it uses less digits than its factorization.

6481781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1243.

The product of its digits is 10752, while the sum is 35.

The square root of 6481781 is about 2545.9342096763. The cubic root of 6481781 is about 186.4510289812.

The spelling of 6481781 in words is "six million, four hundred eighty-one thousand, seven hundred eighty-one".