21106965600 has 648 divisors, whose sum is σ = 89608952160. Its totient is φ = 4655831040.

The previous prime is 21106965589. The next prime is 21106965601. The reversal of 21106965600 is 656960112.

21106965600 is a `hidden beast` number, since 2 + 1 + 1 + 0 + 6 + 96 + 560 + 0 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21106965601) by changing a digit.

It is a polite number, since it can be written in 107 ways as a sum of consecutive naturals, for example, 10230169 + ... + 10232231.

It is an arithmetic number, because the mean of its divisors is an integer number (138285420).

Almost surely, 2^21106965600 is an apocalyptic number.

21106965600 is a gapful number since it is divisible by the number (20) 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 21106965600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44804476080).

21106965600 is an abundant number, since it is smaller than the sum of its proper divisors (68501986560).

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

21106965600 is a wasteful number, since it uses less digits than its factorization.

21106965600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2132 (or 2109 counting only the distinct ones).

The product of its (nonzero) digits is 19440, while the sum is 36.

The spelling of 21106965600 in words is "twenty-one billion, one hundred six million, nine hundred sixty-five thousand, six hundred".