21121200002021 has 32 divisors (see below), whose sum is σ = 25727911046400. Its totient is φ = 16957540615680.

The previous prime is 21121200002009. The next prime is 21121200002099. The reversal of 21121200002021 is 12020000212112.

It is not a de Polignac number, because 21121200002021 - 2¹⁰ = 21121200000997 is a prime.

It is a super-2 number, since 2×21121200002021² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21121200001987 and 21121200002005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21121200002921) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10778651 + ... + 12586568.

It is an arithmetic number, because the mean of its divisors is an integer number (803997220200).

Almost surely, 2^{21121200002021} is an apocalyptic number.

It is an amenable number.

21121200002021 is a deficient number, since it is larger than the sum of its proper divisors (4606711044379).

21121200002021 is a wasteful number, since it uses less digits than its factorization.

21121200002021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23365389.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21121200002021 its reverse (12020000212112), we get a palindrome (33141200214133).

The spelling of 21121200002021 in words is "twenty-one trillion, one hundred twenty-one billion, two hundred million, two thousand, twenty-one".