1213543605 has 16 divisors (see below), whose sum is σ = 1968269760. Its totient is φ = 638356608.

The previous prime is 1213543561. The next prime is 1213543613. The reversal of 1213543605 is 5063453121.

It is not a de Polignac number, because 1213543605 - 2¹⁶ = 1213478069 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 553035 + ... + 555224.

It is an arithmetic number, because the mean of its divisors is an integer number (123016860).

Almost surely, 2^1213543605 is an apocalyptic number.

1213543605 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1213543605 is a deficient number, since it is larger than the sum of its proper divisors (754726155).

1213543605 is a wasteful number, since it uses less digits than its factorization.

1213543605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1108340.

The product of its (nonzero) digits is 10800, while the sum is 30.

The square root of 1213543605 is about 34835.9527643496. The cubic root of 1213543605 is about 1066.6414635430.

Adding to 1213543605 its reverse (5063453121), we get a palindrome (6276996726).

The spelling of 1213543605 in words is "one billion, two hundred thirteen million, five hundred forty-three thousand, six hundred five".