4257840 has 80 divisors (see below), whose sum is σ = 13400928. Its totient is φ = 1118208.

The previous prime is 4257833. The next prime is 4257889. The reversal of 4257840 is 487524.

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 = 4257798 and 4257807.

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, 27042 + ... + 27198.

Almost surely, 2^4257840 is an apocalyptic number.

4257840 is a gapful number since it is divisible by the number (40) 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 4257840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6700464).

4257840 is an abundant number, since it is smaller than the sum of its proper divisors (9143088).

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

4257840 is a wasteful number, since it uses less digits than its factorization.

4257840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 286 (or 280 counting only the distinct ones).

The product of its (nonzero) digits is 8960, while the sum is 30.

The square root of 4257840 is about 2063.4534159995. The cubic root of 4257840 is about 162.0801310634.

The spelling of 4257840 in words is "four million, two hundred fifty-seven thousand, eight hundred forty".