421420355325521 has 2 divisors, whose sum is σ = 421420355325522. Its totient is φ = 421420355325520.

The previous prime is 421420355325427. The next prime is 421420355325523. The reversal of 421420355325521 is 125523553024124.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 348453566281921 + 72966789043600 = 18666911^2 + 8542060^2 .

It is a cyclic number.

It is not a de Polignac number, because 421420355325521 - 2⁴⁶ = 351051611147857 is a prime.

Together with 421420355325523, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (421420355325523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210710177662760 + 210710177662761.

It is an arithmetic number, because the mean of its divisors is an integer number (210710177662761).

Almost surely, 2^{421420355325521} is an apocalyptic number.

It is an amenable number.

421420355325521 is a deficient number, since it is larger than the sum of its proper divisors (1).

421420355325521 is an equidigital number, since it uses as much as digits as its factorization.

421420355325521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1440000, while the sum is 44.

The spelling of 421420355325521 in words is "four hundred twenty-one trillion, four hundred twenty billion, three hundred fifty-five million, three hundred twenty-five thousand, five hundred twenty-one".