1213947643 has 2 divisors, whose sum is σ = 1213947644. Its totient is φ = 1213947642.

The previous prime is 1213947599. The next prime is 1213947653. The reversal of 1213947643 is 3467493121.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1213947643 - 2⁹ = 1213947131 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1213947596 and 1213947605.

It is not a weakly prime, because it can be changed into another prime (1213947653) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 606973821 + 606973822.

It is an arithmetic number, because the mean of its divisors is an integer number (606973822).

Almost surely, 2^1213947643 is an apocalyptic number.

1213947643 is a deficient number, since it is larger than the sum of its proper divisors (1).

1213947643 is an equidigital number, since it uses as much as digits as its factorization.

1213947643 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 108864, while the sum is 40.

The square root of 1213947643 is about 34841.7514341630. The cubic root of 1213947643 is about 1066.7598265097.

The spelling of 1213947643 in words is "one billion, two hundred thirteen million, nine hundred forty-seven thousand, six hundred forty-three".