6731640 has 128 divisors (see below), whose sum is σ = 23500800. Its totient is φ = 1710720.

The previous prime is 6731639. The next prime is 6731651. The reversal of 6731640 is 461376.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an Ulam number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 24705 + ... + 24975.

It is an arithmetic number, because the mean of its divisors is an integer number (183600).

Almost surely, 2^6731640 is an apocalyptic number.

6731640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6731640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11750400).

6731640 is an abundant number, since it is smaller than the sum of its proper divisors (16769160).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6731640 is a wasteful number, since it uses less digits than its factorization.

6731640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 314 (or 304 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 27.

The square root of 6731640 is about 2594.5404217318. The cubic root of 6731640 is about 188.8166526296.

The spelling of 6731640 in words is "six million, seven hundred thirty-one thousand, six hundred forty".