1211533450 has 12 divisors (see below), whose sum is σ = 2253452310. Its totient is φ = 484613360.

The previous prime is 1211533447. The next prime is 1211533451. The reversal of 1211533450 is 543351121.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 1007872009 + 203661441 = 31747^2 + 14271^2 .

It is a Harshad number since it is a multiple of its sum of digits (25).

It is not an unprimeable number, because it can be changed into a prime (1211533451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 12115285 + ... + 12115384.

Almost surely, 2^1211533450 is an apocalyptic number.

1211533450 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1211533450 is a deficient number, since it is larger than the sum of its proper divisors (1041918860).

1211533450 is a wasteful number, since it uses less digits than its factorization.

1211533450 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24230681 (or 24230676 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 25.

The square root of 1211533450 is about 34807.0890767958. The cubic root of 1211533450 is about 1066.0521976348.

Adding to 1211533450 its reverse (543351121), we get a palindrome (1754884571).

The spelling of 1211533450 in words is "one billion, two hundred eleven million, five hundred thirty-three thousand, four hundred fifty".