221212321424 has 40 divisors (see below), whose sum is σ = 430579639800. Its totient is φ = 110096179200.

The previous prime is 221212321403. The next prime is 221212321427. The reversal of 221212321424 is 424123212122.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 17150521600 + 204061799824 = 130960^2 + 451732^2 .

It is a super-2 number, since 2×221212321424² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 221212321393 and 221212321402.

It is not an unprimeable number, because it can be changed into a prime (221212321427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2987894 + ... + 3061034.

It is an arithmetic number, because the mean of its divisors is an integer number (10764490995).

Almost surely, 2^221212321424 is an apocalyptic number.

It is an amenable number.

221212321424 is a deficient number, since it is larger than the sum of its proper divisors (209367318376).

221212321424 is a wasteful number, since it uses less digits than its factorization.

221212321424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74019 (or 74013 counting only the distinct ones).

The product of its digits is 3072, while the sum is 26.

Adding to 221212321424 its reverse (424123212122), we get a palindrome (645335533546).

The spelling of 221212321424 in words is "two hundred twenty-one billion, two hundred twelve million, three hundred twenty-one thousand, four hundred twenty-four".