21835681136640 has 768 divisors, whose sum is σ = 87697657756800. Its totient is φ = 4922472923136.

The previous prime is 21835681136603. The next prime is 21835681136651. The reversal of 21835681136640 is 4663118653812.

It is a happy number.

21835681136640 is a `hidden beast` number, since 2 + 1 + 8 + 3 + 568 + 1 + 1 + 36 + 6 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (768).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 753485671 + ... + 753514649.

Almost surely, 2^{21835681136640} is an apocalyptic number.

21835681136640 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 21835681136640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43848828878400).

21835681136640 is an abundant number, since it is smaller than the sum of its proper divisors (65861976620160).

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

21835681136640 is an equidigital number, since it uses as much as digits as its factorization.

21835681136640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29100 (or 29069 counting only the distinct ones).

The product of its (nonzero) digits is 4976640, while the sum is 54.

The spelling of 21835681136640 in words is "twenty-one trillion, eight hundred thirty-five billion, six hundred eighty-one million, one hundred thirty-six thousand, six hundred forty".