21791715379200 has 720 divisors, whose sum is σ = 86920690196340. Its totient is φ = 5364101283840.

The previous prime is 21791715379171. The next prime is 21791715379211. The reversal of 21791715379200 is 297351719712.

21791715379200 is a `hidden beast` number, since 2 + 1 + 7 + 9 + 17 + 1 + 537 + 92 + 0 + 0 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 8306016224256 + 13485699154944 = 2882016^2 + 3672288^2 .

It is a tau number, because it is divible by the number of its divisors (720).

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

It is an unprimeable number.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 53711502 + ... + 54115698.

Almost surely, 2^{21791715379200} is an apocalyptic number.

21791715379200 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 21791715379200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43460345098170).

21791715379200 is an abundant number, since it is smaller than the sum of its proper divisors (65128974817140).

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

21791715379200 is a wasteful number, since it uses less digits than its factorization.

21791715379200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 404254 (or 404220 counting only the distinct ones).

The product of its (nonzero) digits is 1666980, while the sum is 54.

The spelling of 21791715379200 in words is "twenty-one trillion, seven hundred ninety-one billion, seven hundred fifteen million, three hundred seventy-nine thousand, two hundred".