121100221 has 16 divisors (see below), whose sum is σ = 138475008. Its totient is φ = 104830000.

The previous prime is 121100219. The next prime is 121100233. The reversal of 121100221 is 122001121.

It is not a de Polignac number, because 121100221 - 2¹ = 121100219 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 121100198 and 121100207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121100321) 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, 62550 + ... + 64456.

It is an arithmetic number, because the mean of its divisors is an integer number (8654688).

Almost surely, 2^121100221 is an apocalyptic number.

121100221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

121100221 is a deficient number, since it is larger than the sum of its proper divisors (17374787).

121100221 is a wasteful number, since it uses less digits than its factorization.

121100221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2192.

The product of its (nonzero) digits is 8, while the sum is 10.

The square root of 121100221 is about 11004.5545570914. The cubic root of 121100221 is about 494.7452636179.

Adding to 121100221 its reverse (122001121), we get a palindrome (243101342).

The spelling of 121100221 in words is "one hundred twenty-one million, one hundred thousand, two hundred twenty-one".