1211525730 has 24 divisors (see below), whose sum is σ = 3149967132. Its totient is φ = 323073504.

The previous prime is 1211525719. The next prime is 1211525741. The reversal of 1211525730 is 375251121.

It is an interprime number because it is at equal distance from previous prime (1211525719) and next prime (1211525741).

It can be written as a sum of positive squares in 2 ways, for example, as 1188801441 + 22724289 = 34479^2 + 4767^2 .

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1211525694 and 1211525703.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 6730609 + ... + 6730788.

Almost surely, 2^1211525730 is an apocalyptic number.

1211525730 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1211525730 is an abundant number, since it is smaller than the sum of its proper divisors (1938441402).

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

1211525730 is a wasteful number, since it uses less digits than its factorization.

1211525730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13461410 (or 13461407 counting only the distinct ones).

The product of its (nonzero) digits is 2100, while the sum is 27.

The square root of 1211525730 is about 34806.9781796697. The cubic root of 1211525730 is about 1066.0499333032.

Adding to 1211525730 its reverse (375251121), we get a palindrome (1586776851).

The spelling of 1211525730 in words is "one billion, two hundred eleven million, five hundred twenty-five thousand, seven hundred thirty".