1222855920 has 640 divisors, whose sum is σ = 5129671680. Its totient is φ = 263761920.

The previous prime is 1222855919. The next prime is 1222855937. The reversal of 1222855920 is 295582221.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 11428507 + ... + 11428613.

It is an arithmetic number, because the mean of its divisors is an integer number (8015112).

Almost surely, 2^1222855920 is an apocalyptic number.

1222855920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1222855920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2564835840).

1222855920 is an abundant number, since it is smaller than the sum of its proper divisors (3906815760).

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

1222855920 is a wasteful number, since it uses less digits than its factorization.

1222855920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 190 (or 178 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 36.

The square root of 1222855920 is about 34969.3568714096. The cubic root of 1222855920 is about 1069.3628605613.

The spelling of 1222855920 in words is "one billion, two hundred twenty-two million, eight hundred fifty-five thousand, nine hundred twenty".