1213073643 has 4 divisors (see below), whose sum is σ = 1617431528. Its totient is φ = 808715760.

The previous prime is 1213073623. The next prime is 1213073651. The reversal of 1213073643 is 3463703121.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 1213073643 - 2⁵ = 1213073611 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1213073643.

It is not an unprimeable number, because it can be changed into a prime (1213073623) 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 3 ways as a sum of consecutive naturals, for example, 202178938 + ... + 202178943.

It is an arithmetic number, because the mean of its divisors is an integer number (404357882).

Almost surely, 2^1213073643 is an apocalyptic number.

1213073643 is a deficient number, since it is larger than the sum of its proper divisors (404357885).

1213073643 is an equidigital number, since it uses as much as digits as its factorization.

1213073643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 404357884.

The product of its (nonzero) digits is 9072, while the sum is 30.

The square root of 1213073643 is about 34829.2067523795. The cubic root of 1213073643 is about 1066.5037550786.

Adding to 1213073643 its reverse (3463703121), we get a palindrome (4676776764).

The spelling of 1213073643 in words is "one billion, two hundred thirteen million, seventy-three thousand, six hundred forty-three".