21221746761600 has 2304 divisors, whose sum is σ = 103669989696000. Its totient is φ = 4150119628800.

The previous prime is 21221746761599. The next prime is 21221746761637. The reversal of 21221746761600 is 616764712212.

21221746761600 is a `hidden beast` number, since 2 + 1 + 2 + 21 + 7 + 4 + 6 + 7 + 616 + 0 + 0 = 666.

It is a super-2 number, since 2×21221746761600² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 1017867976 + ... + 1017888824.

It is an arithmetic number, because the mean of its divisors is an integer number (44995655250).

Almost surely, 2^{21221746761600} is an apocalyptic number.

21221746761600 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 21221746761600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (51834994848000).

21221746761600 is an abundant number, since it is smaller than the sum of its proper divisors (82448242934400).

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

21221746761600 is a wasteful number, since it uses less digits than its factorization.

21221746761600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20923 (or 20894 counting only the distinct ones).

The product of its (nonzero) digits is 338688, while the sum is 45.

The spelling of 21221746761600 in words is "twenty-one trillion, two hundred twenty-one billion, seven hundred forty-six million, seven hundred sixty-one thousand, six hundred".