21126226716 has 216 divisors, whose sum is σ = 63207288144. Its totient is φ = 5931394560.

The previous prime is 21126226699. The next prime is 21126226813. The reversal of 21126226716 is 61762262112.

It is a happy number.

21126226716 is a `hidden beast` number, since 2 + 1 + 12 + 622 + 6 + 7 + 16 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

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 71 ways as a sum of consecutive naturals, for example, 45826726 + ... + 45827186.

It is an arithmetic number, because the mean of its divisors is an integer number (292626334).

Almost surely, 2^21126226716 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 21126226716, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31603644072).

21126226716 is an abundant number, since it is smaller than the sum of its proper divisors (42081061428).

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

21126226716 is a wasteful number, since it uses less digits than its factorization.

21126226716 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 881 (or 869 counting only the distinct ones).

The product of its digits is 24192, while the sum is 36.

Adding to 21126226716 its reverse (61762262112), we get a palindrome (82888488828).

The spelling of 21126226716 in words is "twenty-one billion, one hundred twenty-six million, two hundred twenty-six thousand, seven hundred sixteen".