21212121282 has 32 divisors (see below), whose sum is σ = 47876892480. Its totient is φ = 6206262720.

The previous prime is 21212121209. The next prime is 21212121283. The reversal of 21212121282 is 28212121212.

It is not an unprimeable number, because it can be changed into a prime (21212121283) 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, 5539393 + ... + 5543220.

It is an arithmetic number, because the mean of its divisors is an integer number (1496152890).

Almost surely, 2^21212121282 is an apocalyptic number.

21212121282 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21212121282 is an abundant number, since it is smaller than the sum of its proper divisors (26664771198).

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

21212121282 is a wasteful number, since it uses less digits than its factorization.

21212121282 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11082658.

The product of its digits is 512, while the sum is 24.

Adding to 21212121282 its reverse (28212121212), we get a palindrome (49424242494).

The spelling of 21212121282 in words is "twenty-one billion, two hundred twelve million, one hundred twenty-one thousand, two hundred eighty-two".