211221212219990 has 32 divisors (see below), whose sum is σ = 434606729477184. Its totient is φ = 72402947752320.

The previous prime is 211221212219989. The next prime is 211221212220121. The reversal of 211221212219990 is 99912212122112.

It is a super-2 number, since 2×211221212219990² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 327875501 + ... + 328519080.

It is an arithmetic number, because the mean of its divisors is an integer number (13581460296162).

Almost surely, 2^{211221212219990} is an apocalyptic number.

211221212219990 is an abundant number, since it is smaller than the sum of its proper divisors (223385517257194).

211221212219990 is a wasteful number, since it uses less digits than its factorization.

211221212219990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 656399192.

The product of its (nonzero) digits is 46656, while the sum is 44.

The spelling of 211221212219990 in words is "two hundred eleven trillion, two hundred twenty-one billion, two hundred twelve million, two hundred nineteen thousand, nine hundred ninety".