21121000456064 has 32 divisors (see below), whose sum is σ = 42240716870400. Its totient is φ = 10519408771072.

The previous prime is 21121000456013. The next prime is 21121000456081. The reversal of 21121000456064 is 46065400012112.

It is a tau number, because it is divible by the number of its divisors (32).

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a self number, because there is not a number n which added to its sum of digits gives 21121000456064.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 320993984 + ... + 321059775.

It is an arithmetic number, because the mean of its divisors is an integer number (1320022402200).

Almost surely, 2^{21121000456064} is an apocalyptic number.

It is an amenable number.

21121000456064 is a deficient number, since it is larger than the sum of its proper divisors (21119716414336).

21121000456064 is an equidigital number, since it uses as much as digits as its factorization.

21121000456064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 642054030 (or 642054018 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 32.

Adding to 21121000456064 its reverse (46065400012112), we get a palindrome (67186400468176).

The spelling of 21121000456064 in words is "twenty-one trillion, one hundred twenty-one billion, four hundred fifty-six thousand, sixty-four".