6455640 has 64 divisors (see below), whose sum is σ = 20217600. Its totient is φ = 1645952.

The previous prime is 6455639. The next prime is 6455677. The reversal of 6455640 is 465546.

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 = 6455598 and 6455607.

It is a congruent number.

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, 1591 + ... + 3929.

It is an arithmetic number, because the mean of its divisors is an integer number (315900).

Almost surely, 2^6455640 is an apocalyptic number.

6455640 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 6455640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10108800).

6455640 is an abundant number, since it is smaller than the sum of its proper divisors (13761960).

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

6455640 is a wasteful number, since it uses less digits than its factorization.

6455640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2376 (or 2372 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 30.

The square root of 6455640 is about 2540.7951511289. The cubic root of 6455640 is about 186.2000391496.

The spelling of 6455640 in words is "six million, four hundred fifty-five thousand, six hundred forty".