21010121120121 has 8 divisors (see below), whose sum is σ = 32015422659264. Its totient is φ = 12005783497200.

The previous prime is 21010121120119. The next prime is 21010121120129. The reversal of 21010121120121 is 12102112101012.

It is a happy number.

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

It is not a de Polignac number, because 21010121120121 - 2¹ = 21010121120119 is a prime.

It is a super-2 number, since 2×21010121120121² (a number of 27 digits) contains 22 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21010121120121.

It is not an unprimeable number, because it can be changed into a prime (21010121120129) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 500240979030 + ... + 500240979071.

It is an arithmetic number, because the mean of its divisors is an integer number (4001927832408).

Almost surely, 2^{21010121120121} is an apocalyptic number.

21010121120121 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21010121120121 is a deficient number, since it is larger than the sum of its proper divisors (11005301539143).

21010121120121 is a wasteful number, since it uses less digits than its factorization.

21010121120121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1000481958111.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 21010121120121 its reverse (12102112101012), we get a palindrome (33112233221133).

The spelling of 21010121120121 in words is "twenty-one trillion, ten billion, one hundred twenty-one million, one hundred twenty thousand, one hundred twenty-one".