7856867869 has 2 divisors, whose sum is σ = 7856867870. Its totient is φ = 7856867868.

The previous prime is 7856867839. The next prime is 7856867911. The reversal of 7856867869 is 9687686587.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7680243769 + 176624100 = 87637^2 + 13290^2 .

It is an emirp because it is prime and its reverse (9687686587) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7856867869 - 2⁹ = 7856867357 is a prime.

It is a super-2 number, since 2×7856867869² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 7856867798 and 7856867807.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7856867839) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3928433934 + 3928433935.

It is an arithmetic number, because the mean of its divisors is an integer number (3928433935).

Almost surely, 2^7856867869 is an apocalyptic number.

It is an amenable number.

7856867869 is a deficient number, since it is larger than the sum of its proper divisors (1).

7856867869 is an equidigital number, since it uses as much as digits as its factorization.

7856867869 is an evil number, because the sum of its binary digits is even.

The product of its digits is 243855360, while the sum is 70.

The square root of 7856867869 is about 88638.9748868972. The cubic root of 7856867869 is about 1988.0004720643. Note that the first 3 decimals are identical.

The spelling of 7856867869 in words is "seven billion, eight hundred fifty-six million, eight hundred sixty-seven thousand, eight hundred sixty-nine".