1212222100 has 18 divisors (see below), whose sum is σ = 2630522174. Its totient is φ = 484888800.

The previous prime is 1212222091. The next prime is 1212222133. The reversal of 1212222100 is 12222121.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 31337604 + 1180884496 = 5598^2 + 34364^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6061011 + ... + 6061210.

Almost surely, 2^1212222100 is an apocalyptic number.

1212222100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1212222100 is an abundant number, since it is smaller than the sum of its proper divisors (1418300074).

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

1212222100 is a wasteful number, since it uses less digits than its factorization.

1212222100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12122235 (or 12122228 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

The square root of 1212222100 is about 34816.9800528420. The cubic root of 1212222100 is about 1066.2541449528.

Adding to 1212222100 its reverse (12222121), we get a palindrome (1224444221).

The spelling of 1212222100 in words is "one billion, two hundred twelve million, two hundred twenty-two thousand, one hundred".