221020311421 has 16 divisors (see below), whose sum is σ = 281405174400. Its totient is φ = 168843100608.

The previous prime is 221020311403. The next prime is 221020311439. The reversal of 221020311421 is 124113020122.

It is an interprime number because it is at equal distance from previous prime (221020311403) and next prime (221020311439).

It is not a de Polignac number, because 221020311421 - 2²⁵ = 220986756989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221020311461) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 41873131 + ... + 41878408.

It is an arithmetic number, because the mean of its divisors is an integer number (17587823400).

Almost surely, 2^221020311421 is an apocalyptic number.

It is an amenable number.

221020311421 is a deficient number, since it is larger than the sum of its proper divisors (60384862979).

221020311421 is a wasteful number, since it uses less digits than its factorization.

221020311421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83751588.

The product of its (nonzero) digits is 192, while the sum is 19.

Adding to 221020311421 its reverse (124113020122), we get a palindrome (345133331543).

The spelling of 221020311421 in words is "two hundred twenty-one billion, twenty million, three hundred eleven thousand, four hundred twenty-one".