1212326440 has 128 divisors (see below), whose sum is σ = 3218292000. Its totient is φ = 406683648.

The previous prime is 1212326419. The next prime is 1212326441. The reversal of 1212326440 is 446232121.

It is a happy number.

It can be written as a sum of positive squares in 16 ways, for example, as 1425636 + 1210900804 = 1194^2 + 34798^2 .

It is not an unprimeable number, because it can be changed into a prime (1212326441) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 253996 + ... + 258724.

Almost surely, 2^1212326440 is an apocalyptic number.

1212326440 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 1212326440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1609146000).

1212326440 is an abundant number, since it is smaller than the sum of its proper divisors (2005965560).

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

1212326440 is a wasteful number, since it uses less digits than its factorization.

1212326440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4799 (or 4795 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 1212326440 is about 34818.4784274098. The cubic root of 1212326440 is about 1066.2847360922.

Adding to 1212326440 its reverse (446232121), we get a palindrome (1658558561).

The spelling of 1212326440 in words is "one billion, two hundred twelve million, three hundred twenty-six thousand, four hundred forty".