6842640 has 80 divisors (see below), whose sum is σ = 24248448. Its totient is φ = 1563648.

The previous prime is 6842639. The next prime is 6842651. The reversal of 6842640 is 462486.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 6842598 and 6842607.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 357 + ... + 3716.

Almost surely, 2^6842640 is an apocalyptic number.

6842640 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 6842640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12124224).

6842640 is an abundant number, since it is smaller than the sum of its proper divisors (17405808).

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

6842640 is a wasteful number, since it uses less digits than its factorization.

6842640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4096 (or 4090 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 30.

The square root of 6842640 is about 2615.8440320478. The cubic root of 6842640 is about 189.8488178718.

The spelling of 6842640 in words is "six million, eight hundred forty-two thousand, six hundred forty".