1211859912 has 64 divisors (see below), whose sum is σ = 3078000000. Its totient is φ = 397558784.

The previous prime is 1211859911. The next prime is 1211859947. The reversal of 1211859912 is 2199581121.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (1211859911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 402589 + ... + 405587.

It is an arithmetic number, because the mean of its divisors is an integer number (48093750).

Almost surely, 2^1211859912 is an apocalyptic number.

1211859912 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1211859912 is an abundant number, since it is smaller than the sum of its proper divisors (1866140088).

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

1211859912 is a wasteful number, since it uses less digits than its factorization.

1211859912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3270 (or 3266 counting only the distinct ones).

The product of its digits is 12960, while the sum is 39.

The square root of 1211859912 is about 34811.7783515867. The cubic root of 1211859912 is about 1066.1479424882.

The spelling of 1211859912 in words is "one billion, two hundred eleven million, eight hundred fifty-nine thousand, nine hundred twelve".