1243664348809 has 27 divisors (see below), whose sum is σ = 1281911230119. Its totient is φ = 1206553938240.

The previous prime is 1243664348791. The next prime is 1243664348819. The reversal of 1243664348809 is 9088434663421.

The square root of 1243664348809 is 1115197.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 21914361225 + 1221749987584 = 148035^2 + 1105328^2 .

It is not a de Polignac number, because 1243664348809 - 2¹⁹ = 1243663824521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1243664348819) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 8947225462 + ... + 8947225600.

Almost surely, 2^{1243664348809} is an apocalyptic number.

1243664348809 is the 1115197-th square number.

1243664348809 is the 557599-th centered octagonal number.

It is an amenable number.

1243664348809 is a deficient number, since it is larger than the sum of its proper divisors (38246881310).

1243664348809 is an frugal number, since it uses more digits than its factorization.

1243664348809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 646 (or 323 counting only the distinct ones).

The product of its (nonzero) digits is 23887872, while the sum is 58.

The spelling of 1243664348809 in words is "one trillion, two hundred forty-three billion, six hundred sixty-four million, three hundred forty-eight thousand, eight hundred nine".