1213523345205 has 12 divisors (see below), whose sum is σ = 2103440465100. Its totient is φ = 647212450752.

The previous prime is 1213523345189. The next prime is 1213523345249. The reversal of 1213523345205 is 5025433253121.

1213523345205 is a `hidden beast` number, since 1 + 213 + 5 + 233 + 4 + 5 + 205 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 353599108164 + 859924237041 = 594642^2 + 927321^2 .

It is not a de Polignac number, because 1213523345205 - 2⁴ = 1213523345189 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1213523345205.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13483592680 + ... + 13483592769.

It is an arithmetic number, because the mean of its divisors is an integer number (175286705425).

Almost surely, 2^{1213523345205} is an apocalyptic number.

1213523345205 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1213523345205 is a deficient number, since it is larger than the sum of its proper divisors (889917119895).

1213523345205 is a wasteful number, since it uses less digits than its factorization.

1213523345205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26967185460 (or 26967185457 counting only the distinct ones).

The product of its (nonzero) digits is 108000, while the sum is 36.

Adding to 1213523345205 its reverse (5025433253121), we get a palindrome (6238956598326).

The spelling of 1213523345205 in words is "one trillion, two hundred thirteen billion, five hundred twenty-three million, three hundred forty-five thousand, two hundred five".