21212221101984 has 240 divisors, whose sum is σ = 69638574852000. Its totient is φ = 6278458314240.

The previous prime is 21212221101959. The next prime is 21212221101991. The reversal of 21212221101984 is 48910112221212.

21212221101984 is a `hidden beast` number, since 21 + 212 + 221 + 10 + 198 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 7424859 + ... + 9876890.

It is an arithmetic number, because the mean of its divisors is an integer number (290160728550).

Almost surely, 2^{21212221101984} is an apocalyptic number.

21212221101984 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21212221101984 is an abundant number, since it is smaller than the sum of its proper divisors (48426353750016).

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

21212221101984 is a wasteful number, since it uses less digits than its factorization.

21212221101984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17301825 (or 17301808 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 36.

The spelling of 21212221101984 in words is "twenty-one trillion, two hundred twelve billion, two hundred twenty-one million, one hundred one thousand, nine hundred eighty-four".