1213356645 has 32 divisors (see below), whose sum is σ = 2159136000. Its totient is φ = 646506432.

The previous prime is 1213356643. The next prime is 1213356649. The reversal of 1213356645 is 5466533121.

1213356645 is a `hidden beast` number, since 1 + 2 + 1 + 3 + 3 + 5 + 6 + 645 = 666.

It is not a de Polignac number, because 1213356645 - 2¹ = 1213356643 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1213356643) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 161431 + ... + 168779.

It is an arithmetic number, because the mean of its divisors is an integer number (67473000).

Almost surely, 2^1213356645 is an apocalyptic number.

1213356645 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1213356645 is a deficient number, since it is larger than the sum of its proper divisors (945779355).

1213356645 is a wasteful number, since it uses less digits than its factorization.

1213356645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8586 (or 8580 counting only the distinct ones).

The product of its digits is 64800, while the sum is 36.

The square root of 1213356645 is about 34833.2692264163. The cubic root of 1213356645 is about 1066.5866847038.

Adding to 1213356645 its reverse (5466533121), we get a palindrome (6679889766).

The spelling of 1213356645 in words is "one billion, two hundred thirteen million, three hundred fifty-six thousand, six hundred forty-five".