21366955008 has 704 divisors, whose sum is σ = 77347123200. Its totient is φ = 5768921088.

The previous prime is 21366954907. The next prime is 21366955031. The reversal of 21366955008 is 80055966312.

21366955008 is a `hidden beast` number, since 2 + 1 + 36 + 69 + 550 + 0 + 8 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 454616041 + ... + 454616087.

Almost surely, 2^21366955008 is an apocalyptic number.

21366955008 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 21366955008, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38673561600).

21366955008 is an abundant number, since it is smaller than the sum of its proper divisors (55980168192).

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

21366955008 is an frugal number, since it uses more digits than its factorization.

21366955008 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124 (or 88 counting only the distinct ones).

The product of its (nonzero) digits is 388800, while the sum is 45.

The spelling of 21366955008 in words is "twenty-one billion, three hundred sixty-six million, nine hundred fifty-five thousand, eight".