1243947656753 has 4 divisors (see below), whose sum is σ = 1253742520320. Its totient is φ = 1234152793188.

The previous prime is 1243947656717. The next prime is 1243947656761. The reversal of 1243947656753 is 3576567493421.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1243947656753 - 2¹⁰ = 1243947655729 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1243947616753) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4897431593 + ... + 4897431846.

It is an arithmetic number, because the mean of its divisors is an integer number (313435630080).

Almost surely, 2^{1243947656753} is an apocalyptic number.

It is an amenable number.

1243947656753 is a deficient number, since it is larger than the sum of its proper divisors (9794863567).

1243947656753 is an equidigital number, since it uses as much as digits as its factorization.

1243947656753 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9794863566.

The product of its digits is 114307200, while the sum is 62.

The spelling of 1243947656753 in words is "one trillion, two hundred forty-three billion, nine hundred forty-seven million, six hundred fifty-six thousand, seven hundred fifty-three".