21229412568 has 256 divisors, whose sum is σ = 67447296000. Its totient is φ = 5419713024.

The previous prime is 21229412549. The next prime is 21229412599. The reversal of 21229412568 is 86521492212.

It is a Harshad number since it is a multiple of its sum of digits (42).

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 63 ways as a sum of consecutive naturals, for example, 8632123 + ... + 8634581.

It is an arithmetic number, because the mean of its divisors is an integer number (263466000).

Almost surely, 2^21229412568 is an apocalyptic number.

21229412568 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21229412568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33723648000).

21229412568 is an abundant number, since it is smaller than the sum of its proper divisors (46217883432).

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

21229412568 is a wasteful number, since it uses less digits than its factorization.

21229412568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2614 (or 2610 counting only the distinct ones).

The product of its digits is 138240, while the sum is 42.

The spelling of 21229412568 in words is "twenty-one billion, two hundred twenty-nine million, four hundred twelve thousand, five hundred sixty-eight".