21100121020021 has 8 divisors (see below), whose sum is σ = 22341365265600. Its totient is φ = 19858883514048.

The previous prime is 21100121019977. The next prime is 21100121020037. The reversal of 21100121020021 is 12002012100112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21100121020021 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21100121019983 and 21100121020010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21100121020621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5680840 + ... + 8629726.

It is an arithmetic number, because the mean of its divisors is an integer number (2792670658200).

Almost surely, 2^{21100121020021} is an apocalyptic number.

It is an amenable number.

21100121020021 is a deficient number, since it is larger than the sum of its proper divisors (1241244245579).

21100121020021 is a wasteful number, since it uses less digits than its factorization.

21100121020021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3369803.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21100121020021 its reverse (12002012100112), we get a palindrome (33102133120133).

The spelling of 21100121020021 in words is "twenty-one trillion, one hundred billion, one hundred twenty-one million, twenty thousand, twenty-one".