21335124412 has 48 divisors (see below), whose sum is σ = 43924446720. Its totient is φ = 8877419712.

The previous prime is 21335124407. The next prime is 21335124427. The reversal of 21335124412 is 21442153312.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 148014 + ... + 254122.

It is an arithmetic number, because the mean of its divisors is an integer number (915092640).

Almost surely, 2^21335124412 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21335124412, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21962223360).

21335124412 is an abundant number, since it is smaller than the sum of its proper divisors (22589322308).

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

21335124412 is a wasteful number, since it uses less digits than its factorization.

21335124412 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106330 (or 106328 counting only the distinct ones).

The product of its digits is 5760, while the sum is 28.

Adding to 21335124412 its reverse (21442153312), we get a palindrome (42777277724).

The spelling of 21335124412 in words is "twenty-one billion, three hundred thirty-five million, one hundred twenty-four thousand, four hundred twelve".