20211220212 has 48 divisors (see below), whose sum is σ = 48807480960. Its totient is φ = 6501857152.

The previous prime is 20211220193. The next prime is 20211220213. The reversal of 20211220212 is 21202211202.

It is a junction number, because it is equal to n+sod(n) for n = 20211220191 and 20211220200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20211220213) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 850273 + ... + 873719.

It is an arithmetic number, because the mean of its divisors is an integer number (1016822520).

Almost surely, 2^20211220212 is an apocalyptic number.

It is an amenable number.

20211220212 is an abundant number, since it is smaller than the sum of its proper divisors (28596260748).

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

20211220212 is a wasteful number, since it uses less digits than its factorization.

20211220212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25960 (or 25958 counting only the distinct ones).

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

Adding to 20211220212 its reverse (21202211202), we get a palindrome (41413431414).

The spelling of 20211220212 in words is "twenty billion, two hundred eleven million, two hundred twenty thousand, two hundred twelve".