1205642809947 has 32 divisors (see below), whose sum is σ = 1705797460224. Its totient is φ = 754832332800.

The previous prime is 1205642809919. The next prime is 1205642809997. The reversal of 1205642809947 is 7499082465021.

It is not a de Polignac number, because 1205642809947 - 2¹⁵ = 1205642777179 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1205642809997) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 104914872 + ... + 104926362.

It is an arithmetic number, because the mean of its divisors is an integer number (53306170632).

Almost surely, 2^{1205642809947} is an apocalyptic number.

1205642809947 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

1205642809947 is a deficient number, since it is larger than the sum of its proper divisors (500154650277).

1205642809947 is a wasteful number, since it uses less digits than its factorization.

1205642809947 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15819.

The product of its (nonzero) digits is 8709120, while the sum is 57.

The spelling of 1205642809947 in words is "one trillion, two hundred five billion, six hundred forty-two million, eight hundred nine thousand, nine hundred forty-seven".