7857782009 has 16 divisors (see below), whose sum is σ = 10112741376. Its totient is φ = 5925430800.

The previous prime is 7857781993. The next prime is 7857782057. The reversal of 7857782009 is 9002877587.

It is a cyclic number.

It is not a de Polignac number, because 7857782009 - 2⁴ = 7857781993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7857382009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1643567 + ... + 1648340.

It is an arithmetic number, because the mean of its divisors is an integer number (632046336).

Almost surely, 2^7857782009 is an apocalyptic number.

It is an amenable number.

7857782009 is a deficient number, since it is larger than the sum of its proper divisors (2254959367).

7857782009 is a wasteful number, since it uses less digits than its factorization.

7857782009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3291956.

The product of its (nonzero) digits is 1975680, while the sum is 53.

The square root of 7857782009 is about 88644.1312721829. The cubic root of 7857782009 is about 1988.0775698046.

It can be divided in two parts, 785778 and 2009, that added together give a palindrome (787787).

The spelling of 7857782009 in words is "seven billion, eight hundred fifty-seven million, seven hundred eighty-two thousand, nine".