221021212220100 has 216 divisors, whose sum is σ = 694420843596480. Its totient is φ = 58799308458240.

The previous prime is 221021212220093. The next prime is 221021212220111. The reversal of 221021212220100 is 1022212120122.

It is a happy number.

221021212220100 is a `hidden beast` number, since 2 + 210 + 21 + 212 + 220 + 1 + 0 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 6121266247 + ... + 6121302353.

Almost surely, 2^{221021212220100} is an apocalyptic number.

221021212220100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221021212220100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (347210421798240).

221021212220100 is an abundant number, since it is smaller than the sum of its proper divisors (473399631376380).

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

221021212220100 is a wasteful number, since it uses less digits than its factorization.

221021212220100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52059 (or 52049 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 221021212220100 its reverse (1022212120122), we get a palindrome (222043424340222).

The spelling of 221021212220100 in words is "two hundred twenty-one trillion, twenty-one billion, two hundred twelve million, two hundred twenty thousand, one hundred".