1222155220 has 48 divisors (see below), whose sum is σ = 3015226368. Its totient is φ = 410232960.

The previous prime is 1222155203. The next prime is 1222155239. The reversal of 1222155220 is 225512221.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a junction number, because it is equal to n+sod(n) for n = 1222155191 and 1222155200.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 210804 + ... + 216523.

It is an arithmetic number, because the mean of its divisors is an integer number (62817216).

Almost surely, 2^1222155220 is an apocalyptic number.

1222155220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1222155220 is an abundant number, since it is smaller than the sum of its proper divisors (1793071148).

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

1222155220 is a wasteful number, since it uses less digits than its factorization.

1222155220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 427360 (or 427358 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 22.

The square root of 1222155220 is about 34959.3366641874. The cubic root of 1222155220 is about 1069.1585721936.

Adding to 1222155220 its reverse (225512221), we get a palindrome (1447667441).

The spelling of 1222155220 in words is "one billion, two hundred twenty-two million, one hundred fifty-five thousand, two hundred twenty".