211221212220100 has 72 divisors (see below), whose sum is σ = 458720955106568. Its totient is φ = 84420133632000.

The previous prime is 211221212219989. The next prime is 211221212220121. The reversal of 211221212220100 is 1022212122112.

It can be written as a sum of positive squares in 12 ways, for example, as 81757185313024 + 129464026907076 = 9041968^2 + 11378226^2 .

It is a super-2 number, since 2×211221212220100² (a number of 29 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 788296150 + ... + 788564050.

Almost surely, 2^{211221212220100} is an apocalyptic number.

211221212220100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

211221212220100 is an abundant number, since it is smaller than the sum of its proper divisors (247499742886468).

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

211221212220100 is a wasteful number, since it uses less digits than its factorization.

211221212220100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 274265 (or 274258 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 211221212220100 its reverse (1022212122112), we get a palindrome (212243424342212).

The spelling of 211221212220100 in words is "two hundred eleven trillion, two hundred twenty-one billion, two hundred twelve million, two hundred twenty thousand, one hundred".