1222257780 has 72 divisors (see below), whose sum is σ = 3835377000. Its totient is φ = 314694912.

The previous prime is 1222257763. The next prime is 1222257787. The reversal of 1222257780 is 877522221.

1222257780 is a `hidden beast` number, since 1 + 2 + 2 + 2 + 2 + 577 + 80 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 33663204 + 1188594576 = 5802^2 + 34476^2 .

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1222257787) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 111855 + ... + 122294.

It is an arithmetic number, because the mean of its divisors is an integer number (53269125).

Almost surely, 2^1222257780 is an apocalyptic number.

1222257780 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1222257780 is an abundant number, since it is smaller than the sum of its proper divisors (2613119220).

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

1222257780 is a wasteful number, since it uses less digits than its factorization.

1222257780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 234193 (or 234188 counting only the distinct ones).

The product of its (nonzero) digits is 31360, while the sum is 36.

The square root of 1222257780 is about 34960.8034804694. The cubic root of 1222257780 is about 1069.1884783338.

The spelling of 1222257780 in words is "one billion, two hundred twenty-two million, two hundred fifty-seven thousand, seven hundred eighty".