1211713245 has 12 divisors (see below), whose sum is σ = 2100303036. Its totient is φ = 646247040.

The previous prime is 1211713187. The next prime is 1211713247. The reversal of 1211713245 is 5423171121.

It can be written as a sum of positive squares in 2 ways, for example, as 355624164 + 856089081 = 18858^2 + 29259^2 .

It is not a de Polignac number, because 1211713245 - 2²² = 1207518941 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211713247) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13463436 + ... + 13463525.

It is an arithmetic number, because the mean of its divisors is an integer number (175025253).

Almost surely, 2^1211713245 is an apocalyptic number.

1211713245 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1211713245 is a deficient number, since it is larger than the sum of its proper divisors (888589791).

1211713245 is a wasteful number, since it uses less digits than its factorization.

1211713245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26926972 (or 26926969 counting only the distinct ones).

The product of its digits is 1680, while the sum is 27.

The square root of 1211713245 is about 34809.6717163492. The cubic root of 1211713245 is about 1066.1049300829.

Adding to 1211713245 its reverse (5423171121), we get a palindrome (6634884366).

The spelling of 1211713245 in words is "one billion, two hundred eleven million, seven hundred thirteen thousand, two hundred forty-five".