1404140021 has 4 divisors (see below), whose sum is σ = 1404753612. Its totient is φ = 1403526432.

The previous prime is 1404139991. The next prime is 1404140027. The reversal of 1404140021 is 1200414041.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 557620996 + 846519025 = 23614^2 + 29095^2 .

It is a cyclic number.

It is not a de Polignac number, because 1404140021 - 2²² = 1399945717 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1404140027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 303350 + ... + 307943.

It is an arithmetic number, because the mean of its divisors is an integer number (351188403).

Almost surely, 2^1404140021 is an apocalyptic number.

It is an amenable number.

1404140021 is a deficient number, since it is larger than the sum of its proper divisors (613591).

1404140021 is an equidigital number, since it uses as much as digits as its factorization.

1404140021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 613590.

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

The square root of 1404140021 is about 37471.8563858264. The cubic root of 1404140021 is about 1119.7905701628.

Adding to 1404140021 its reverse (1200414041), we get a palindrome (2604554062).

The spelling of 1404140021 in words is "one billion, four hundred four million, one hundred forty thousand, twenty-one".