21202120212 has 192 divisors, whose sum is σ = 63720082944. Its totient is φ = 5337446400.

The previous prime is 21202120211. The next prime is 21202120213.

21202120212 is nontrivially palindromic in base 10.

It is an interprime number because it is at equal distance from previous prime (21202120211) and next prime (21202120213).

21202120212 is a modest number, since divided by 2120212 gives 212 as remainder.

It is a junction number, because it is equal to n+sod(n) for n = 21202120191 and 21202120200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21202120211) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2136462 + ... + 2146362.

It is an arithmetic number, because the mean of its divisors is an integer number (331875432).

Almost surely, 2^21202120212 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21202120212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31860041472).

21202120212 is an abundant number, since it is smaller than the sum of its proper divisors (42517962732).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21202120212 is a wasteful number, since it uses less digits than its factorization.

21202120212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10018 (or 10016 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

The spelling of 21202120212 in words is "twenty-one billion, two hundred two million, one hundred twenty thousand, two hundred twelve".