1421404021 has 4 divisors (see below), whose sum is σ = 1421488012. Its totient is φ = 1421320032.

The previous prime is 1421403961. The next prime is 1421404027. The reversal of 1421404021 is 1204041241.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 1213755921 + 207648100 = 34839^2 + 14410^2 .

It is a cyclic number.

It is not a de Polignac number, because 1421404021 - 2²³ = 1413015413 is a prime.

It is a super-3 number, since 3×1421404021³ (a number of 28 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1421404021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1421404027) 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, 6750 + ... + 53743.

It is an arithmetic number, because the mean of its divisors is an integer number (355372003).

Almost surely, 2^1421404021 is an apocalyptic number.

It is an amenable number.

1421404021 is a deficient number, since it is larger than the sum of its proper divisors (83991).

1421404021 is an equidigital number, since it uses as much as digits as its factorization.

1421404021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83990.

The product of its (nonzero) digits is 256, while the sum is 19.

The square root of 1421404021 is about 37701.5121845265. The cubic root of 1421404021 is about 1124.3611901886.

Adding to 1421404021 its reverse (1204041241), we get a palindrome (2625445262).

The spelling of 1421404021 in words is "one billion, four hundred twenty-one million, four hundred four thousand, twenty-one".