10121221 has 16 divisors (see below), whose sum is σ = 11593728.
Its totient is φ = 8751600.
The previous prime is 10121183. The next prime is 10121233. The reversal of 10121221 is 12212101.
It is not a de Polignac number, because 10121221 - 27 = 10121093 is a prime.
It is a super-2 number, since 2×101212212 = 204878229061682, which contains 22 as substring.
It is a Duffinian number.
It is a junction number, because it is equal to n+sod(n) for n = 10121198 and 10121207.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (10121521) 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, 22626 + ... + 23068.
It is an arithmetic number, because the mean of its divisors is an integer number (724608).
Almost surely, 210121221 is an apocalyptic number.
10121221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.
It is an amenable number.
10121221 is a deficient number, since it is larger than the sum of its proper divisors (1472507).
10121221 is a wasteful number, since it uses less digits than its factorization.
10121221 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 552.
The product of its (nonzero) digits is 8, while the sum is 10.
The square root of 10121221 is about 3181.3866473599.
The cubic root of 10121221 is about 216.3105173271.
Adding to 10121221 its reverse (12212101), we get a palindrome (22333322).
The spelling of 10121221 in words is "ten million, one hundred twenty-one thousand, two hundred twenty-one".