421320310021 has 16 divisors (see below), whose sum is σ = 477658137600. Its totient is φ = 368404970688.

The previous prime is 421320310009. The next prime is 421320310051. The reversal of 421320310021 is 120013023124.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-421320310021 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (421320310001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2534940 + ... + 2696026.

It is an arithmetic number, because the mean of its divisors is an integer number (29853633600).

Almost surely, 2^421320310021 is an apocalyptic number.

It is an amenable number.

421320310021 is a deficient number, since it is larger than the sum of its proper divisors (56337827579).

421320310021 is a wasteful number, since it uses less digits than its factorization.

421320310021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171708.

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 421320310021 its reverse (120013023124), we get a palindrome (541333333145).

It can be divided in two parts, 4213203 and 10021, that added together give a palindrome (4223224).

The spelling of 421320310021 in words is "four hundred twenty-one billion, three hundred twenty million, three hundred ten thousand, twenty-one".