6435840 has 88 divisors (see below), whose sum is σ = 20633760. Its totient is φ = 1712128.

The previous prime is 6435833. The next prime is 6435841. The reversal of 6435840 is 485346.

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 = 6435798 and 6435807.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6435841) 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, 15151 + ... + 15569.

Almost surely, 2^6435840 is an apocalyptic number.

6435840 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 6435840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10316880).

6435840 is an abundant number, since it is smaller than the sum of its proper divisors (14197920).

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

6435840 is a wasteful number, since it uses less digits than its factorization.

6435840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 447 (or 429 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 30.

The square root of 6435840 is about 2536.8957408613. The cubic root of 6435840 is about 186.0094803816.

Subtracting from 6435840 its product of nonzero digits (11520), we obtain a triangular number (6424320 = T₃₅₈₄).

The spelling of 6435840 in words is "six million, four hundred thirty-five thousand, eight hundred forty".