12784372991 has 4 divisors (see below), whose sum is σ = 13767786312. Its totient is φ = 11800959672.

The previous prime is 12784372943. The next prime is 12784373009. The reversal of 12784372991 is 19927348721.

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

It is a cyclic number.

It is not a de Polignac number, because 12784372991 - 2²² = 12780178687 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12784372901) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 491706641 + ... + 491706666.

It is an arithmetic number, because the mean of its divisors is an integer number (3441946578).

Almost surely, 2^12784372991 is an apocalyptic number.

12784372991 is a deficient number, since it is larger than the sum of its proper divisors (983413321).

12784372991 is an equidigital number, since it uses as much as digits as its factorization.

12784372991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 983413320.

The product of its digits is 1524096, while the sum is 53.

The spelling of 12784372991 in words is "twelve billion, seven hundred eighty-four million, three hundred seventy-two thousand, nine hundred ninety-one".