21003306126 has 64 divisors (see below), whose sum is σ = 46484582400. Its totient is φ = 6273648000.

The previous prime is 21003306089. The next prime is 21003306131. The reversal of 21003306126 is 62160330012.

It is a happy number.

It is a super-2 number, since 2×21003306126² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21003306096 and 21003306105.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1519635 + ... + 1533393.

It is an arithmetic number, because the mean of its divisors is an integer number (726321600).

Almost surely, 2^21003306126 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21003306126, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23242291200).

21003306126 is an abundant number, since it is smaller than the sum of its proper divisors (25481276274).

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

21003306126 is a wasteful number, since it uses less digits than its factorization.

21003306126 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14105.

The product of its (nonzero) digits is 1296, while the sum is 24.

Adding to 21003306126 its reverse (62160330012), we get a palindrome (83163636138).

The spelling of 21003306126 in words is "twenty-one billion, three million, three hundred six thousand, one hundred twenty-six".