1211543128 has 8 divisors (see below), whose sum is σ = 2271643380. Its totient is φ = 605771560.

The previous prime is 1211543119. The next prime is 1211543149. The reversal of 1211543128 is 8213451121.

It is a tau number, because it is divible by the number of its divisors (8).

It is a junction number, because it is equal to n+sod(n) for n = 1211543096 and 1211543105.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 75721438 + ... + 75721453.

Almost surely, 2^1211543128 is an apocalyptic number.

It is an amenable number.

1211543128 is a deficient number, since it is larger than the sum of its proper divisors (1060100252).

1211543128 is a wasteful number, since it uses less digits than its factorization.

1211543128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151442897 (or 151442893 counting only the distinct ones).

The product of its digits is 1920, while the sum is 28.

The square root of 1211543128 is about 34807.2280999220. The cubic root of 1211543128 is about 1066.0550362484.

Adding to 1211543128 its reverse (8213451121), we get a palindrome (9424994249).

The spelling of 1211543128 in words is "one billion, two hundred eleven million, five hundred forty-three thousand, one hundred twenty-eight".