1421231025421 has 4 divisors (see below), whose sum is σ = 1424775242844. Its totient is φ = 1417686808000.

The previous prime is 1421231025413. The next prime is 1421231025451. The reversal of 1421231025421 is 1245201321241.

It is a happy number.

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 1281141015625 + 140090009796 = 1131875^2 + 374286^2 .

It is a cyclic number.

It is not a de Polignac number, because 1421231025421 - 2³ = 1421231025413 is a prime.

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 1421231025421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1421231025451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1772108110 + ... + 1772108911.

It is an arithmetic number, because the mean of its divisors is an integer number (356193810711).

Almost surely, 2^{1421231025421} is an apocalyptic number.

It is an amenable number.

1421231025421 is a deficient number, since it is larger than the sum of its proper divisors (3544217423).

1421231025421 is an equidigital number, since it uses as much as digits as its factorization.

1421231025421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3544217422.

The product of its (nonzero) digits is 3840, while the sum is 28.

Adding to 1421231025421 its reverse (1245201321241), we get a palindrome (2666432346662).

The spelling of 1421231025421 in words is "one trillion, four hundred twenty-one billion, two hundred thirty-one million, twenty-five thousand, four hundred twenty-one".