1440021 has 12 divisors (see below), whose sum is σ = 2110976. Its totient is φ = 872520.

The previous prime is 1440017. The next prime is 1440037. The reversal of 1440021 is 1200441.

It is not a de Polignac number, because 1440021 - 2² = 1440017 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1439979 and 1440006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1440011) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1621 + ... + 2346.

2^1440021 is an apocalyptic number.

1440021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1440021 is a deficient number, since it is larger than the sum of its proper divisors (670955).

1440021 is a wasteful number, since it uses less digits than its factorization.

1440021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3992 (or 3981 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 12.

The square root of 1440021 is about 1200.0087499681. The cubic root of 1440021 is about 112.9248724007.

Adding to 1440021 its reverse (1200441), we get a palindrome (2640462).

The spelling of 1440021 in words is "one million, four hundred forty thousand, twenty-one".