21227211424 has 24 divisors (see below), whose sum is σ = 42810369588. Its totient is φ = 10354736640.

The previous prime is 21227211373. The next prime is 21227211427. The reversal of 21227211424 is 42411272212.

It can be written as a sum of positive squares in 2 ways, for example, as 21181891600 + 45319824 = 145540^2 + 6732^2 .

It is a super-2 number, since 2×21227211424² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21227211392 and 21227211401.

It is not an unprimeable number, because it can be changed into a prime (21227211427) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8088327 + ... + 8090950.

Almost surely, 2^21227211424 is an apocalyptic number.

It is an amenable number.

21227211424 is an abundant number, since it is smaller than the sum of its proper divisors (21583158164).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21227211424 is a wasteful number, since it uses less digits than its factorization.

21227211424 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16179328 (or 16179320 counting only the distinct ones).

The product of its digits is 3584, while the sum is 28.

Adding to 21227211424 its reverse (42411272212), we get a palindrome (63638483636).

The spelling of 21227211424 in words is "twenty-one billion, two hundred twenty-seven million, two hundred eleven thousand, four hundred twenty-four".