121223220 has 24 divisors (see below), whose sum is σ = 339425184. Its totient is φ = 32326176.

The previous prime is 121223213. The next prime is 121223227. The reversal of 121223220 is 22322121.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (121223213) and next prime (121223227).

It is a super-3 number, since 3×121223220³ (a number of 25 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 121223220.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121223227) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1010134 + ... + 1010253.

It is an arithmetic number, because the mean of its divisors is an integer number (14142716).

Almost surely, 2^121223220 is an apocalyptic number.

121223220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121223220 is an abundant number, since it is smaller than the sum of its proper divisors (218201964).

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

121223220 is a wasteful number, since it uses less digits than its factorization.

121223220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2020399 (or 2020397 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 121223220 is about 11010.1416884616. The cubic root of 121223220 is about 494.9127077986.

Adding to 121223220 its reverse (22322121), we get a palindrome (143545341).

The spelling of 121223220 in words is "one hundred twenty-one million, two hundred twenty-three thousand, two hundred twenty".