4391640 has 96 divisors (see below), whose sum is σ = 15584400. Its totient is φ = 1063680.

The previous prime is 4391617. The next prime is 4391657. The reversal of 4391640 is 461934.

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 23 ways as a sum of consecutive naturals, for example, 3406 + ... + 4514.

Almost surely, 2^4391640 is an apocalyptic number.

4391640 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 4391640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7792200).

4391640 is an abundant number, since it is smaller than the sum of its proper divisors (11192760).

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

4391640 is a wasteful number, since it uses less digits than its factorization.

4391640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1137 (or 1130 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 4391640 is about 2095.6240120785. The cubic root of 4391640 is about 163.7604076286.

It can be divided in two parts, 43916 and 40, that added together give a triangular number (43956 = T₂₉₆).

The spelling of 4391640 in words is "four million, three hundred ninety-one thousand, six hundred forty".