1211743128 has 64 divisors (see below), whose sum is σ = 3132933120. Its totient is φ = 390153600.

The previous prime is 1211743123. The next prime is 1211743129. The reversal of 1211743128 is 8213471121.

It is a junction number, because it is equal to n+sod(n) for n = 1211743095 and 1211743104.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211743123) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 512926 + ... + 515282.

It is an arithmetic number, because the mean of its divisors is an integer number (48952080).

Almost surely, 2^1211743128 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1211743128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1566466560).

1211743128 is an abundant number, since it is smaller than the sum of its proper divisors (1921189992).

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

1211743128 is a wasteful number, since it uses less digits than its factorization.

1211743128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3088 (or 3084 counting only the distinct ones).

The product of its digits is 2688, while the sum is 30.

The square root of 1211743128 is about 34810.1009478571. The cubic root of 1211743128 is about 1066.1136940243.

The spelling of 1211743128 in words is "one billion, two hundred eleven million, seven hundred forty-three thousand, one hundred twenty-eight".