221021021109 has 16 divisors (see below), whose sum is σ = 348407521920. Its totient is φ = 121942632000.

The previous prime is 221021021083. The next prime is 221021021113. The reversal of 221021021109 is 901120120122.

It is not a de Polignac number, because 221021021109 - 2¹⁹ = 221020496821 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221021021119) 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, 181461642 + ... + 181462859.

It is an arithmetic number, because the mean of its divisors is an integer number (21775470120).

Almost surely, 2^221021021109 is an apocalyptic number.

221021021109 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

221021021109 is a deficient number, since it is larger than the sum of its proper divisors (127386500811).

221021021109 is a wasteful number, since it uses less digits than its factorization.

221021021109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 362924540.

The product of its (nonzero) digits is 144, while the sum is 21.

The spelling of 221021021109 in words is "two hundred twenty-one billion, twenty-one million, twenty-one thousand, one hundred nine".