21201021010121 has 8 divisors (see below), whose sum is σ = 22395722404320. Its totient is φ = 20014205434272.

The previous prime is 21201021010111. The next prime is 21201021010123. The reversal of 21201021010121 is 12101012010212.

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

It is a cyclic number.

It is not a de Polignac number, because 21201021010121 - 2¹⁰ = 21201021009097 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21201021010096 and 21201021010105.

It is not an unprimeable number, because it can be changed into a prime (21201021010123) 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, 1971449060 + ... + 1971459813.

It is an arithmetic number, because the mean of its divisors is an integer number (2799465300540).

Almost surely, 2^{21201021010121} is an apocalyptic number.

It is an amenable number.

21201021010121 is a deficient number, since it is larger than the sum of its proper divisors (1194701394199).

21201021010121 is a wasteful number, since it uses less digits than its factorization.

21201021010121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3942909175.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21201021010121 its reverse (12101012010212), we get a palindrome (33302033020333).

The spelling of 21201021010121 in words is "twenty-one trillion, two hundred one billion, twenty-one million, ten thousand, one hundred twenty-one".