1211530745 has 8 divisors (see below), whose sum is σ = 1470172680. Its totient is φ = 958334080.

The previous prime is 1211530741. The next prime is 1211530759. The reversal of 1211530745 is 5470351121.

It can be written as a sum of positive squares in 4 ways, for example, as 257153296 + 954377449 = 16036^2 + 30893^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1211530745 - 2² = 1211530741 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1211530741) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1360826 + ... + 1361715.

It is an arithmetic number, because the mean of its divisors is an integer number (183771585).

Almost surely, 2^1211530745 is an apocalyptic number.

It is an amenable number.

1211530745 is a deficient number, since it is larger than the sum of its proper divisors (258641935).

1211530745 is an equidigital number, since it uses as much as digits as its factorization.

1211530745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2722635.

The product of its (nonzero) digits is 4200, while the sum is 29.

The square root of 1211530745 is about 34807.0502197471. The cubic root of 1211530745 is about 1066.0514042400.

Adding to 1211530745 its reverse (5470351121), we get a palindrome (6681881866).

The spelling of 1211530745 in words is "one billion, two hundred eleven million, five hundred thirty thousand, seven hundred forty-five".