21286804968 has 768 divisors, whose sum is σ = 75504844800. Its totient is φ = 5508518400.

The previous prime is 21286804951. The next prime is 21286804997. The reversal of 21286804968 is 86940868212.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 452910721 + ... + 452910767.

It is an arithmetic number, because the mean of its divisors is an integer number (98313600).

Almost surely, 2^21286804968 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 21286804968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37752422400).

21286804968 is an abundant number, since it is smaller than the sum of its proper divisors (54218039832).

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

21286804968 is a wasteful number, since it uses less digits than its factorization.

21286804968 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171 (or 150 counting only the distinct ones).

The product of its (nonzero) digits is 2654208, while the sum is 54.

The spelling of 21286804968 in words is "twenty-one billion, two hundred eighty-six million, eight hundred four thousand, nine hundred sixty-eight".