21235424412 has 24 divisors (see below), whose sum is σ = 49644442512. Its totient is φ = 7064886400.

The previous prime is 21235424401. The next prime is 21235424417. The reversal of 21235424412 is 21442453212.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21235424412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21235424417) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1692039 + ... + 1704542.

It is an arithmetic number, because the mean of its divisors is an integer number (2068518438).

Almost surely, 2^21235424412 is an apocalyptic number.

It is an amenable number.

21235424412 is an abundant number, since it is smaller than the sum of its proper divisors (28409018100).

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

21235424412 is a wasteful number, since it uses less digits than its factorization.

21235424412 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3397109 (or 3397107 counting only the distinct ones).

The product of its digits is 15360, while the sum is 30.

Adding to 21235424412 its reverse (21442453212), we get a palindrome (42677877624).

The spelling of 21235424412 in words is "twenty-one billion, two hundred thirty-five million, four hundred twenty-four thousand, four hundred twelve".