4001840 has 20 divisors (see below), whose sum is σ = 9304464. Its totient is φ = 1600704.

The previous prime is 4001831. The next prime is 4001849. The reversal of 4001840 is 481004.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (4001831) and next prime (4001849).

It is a tau number, because it is divible by the number of its divisors (20).

It is a hoax number, since the sum of its digits (17) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (4001849) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24932 + ... + 25091.

Almost surely, 2^4001840 is an apocalyptic number.

4001840 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

4001840 is an abundant number, since it is smaller than the sum of its proper divisors (5302624).

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

4001840 is a wasteful number, since it uses less digits than its factorization.

4001840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50036 (or 50030 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 4001840 is about 2000.4599471122. The cubic root of 4001840 is about 158.7644416151.

Adding to 4001840 its reverse (481004), we get a palindrome (4482844).

The spelling of 4001840 in words is "four million, one thousand, eight hundred forty".