21425321512 has 64 divisors (see below), whose sum is σ = 46265281920. Its totient is φ = 9111667968.

The previous prime is 21425321503. The next prime is 21425321549. The reversal of 21425321512 is 21512352412.

It is a happy number.

It is a super-2 number, since 2×21425321512² (a number of 21 digits) contains 22 as substring.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10435078 + ... + 10437130.

It is an arithmetic number, because the mean of its divisors is an integer number (722895030).

Almost surely, 2^21425321512 is an apocalyptic number.

It is an amenable number.

21425321512 is an abundant number, since it is smaller than the sum of its proper divisors (24839960408).

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

21425321512 is a wasteful number, since it uses less digits than its factorization.

21425321512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3410 (or 3406 counting only the distinct ones).

The product of its digits is 4800, while the sum is 28.

Adding to 21425321512 its reverse (21512352412), we get a palindrome (42937673924).

The spelling of 21425321512 in words is "twenty-one billion, four hundred twenty-five million, three hundred twenty-one thousand, five hundred twelve".