861862769 has 2 divisors, whose sum is σ = 861862770. Its totient is φ = 861862768.

The previous prime is 861862711. The next prime is 861862789. The reversal of 861862769 is 967268168.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 835903744 + 25959025 = 28912^2 + 5095^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-861862769 is a prime.

It is a super-2 number, since 2×861862769² = 1485614865176694722, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 861862769.

It is not a weakly prime, because it can be changed into another prime (861862789) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 430931384 + 430931385.

It is an arithmetic number, because the mean of its divisors is an integer number (430931385).

Almost surely, 2^861862769 is an apocalyptic number.

It is an amenable number.

861862769 is a deficient number, since it is larger than the sum of its proper divisors (1).

861862769 is an equidigital number, since it uses as much as digits as its factorization.

861862769 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1741824, while the sum is 53.

The square root of 861862769 is about 29357.4993655795. The cubic root of 861862769 is about 951.6546487762.

The spelling of 861862769 in words is "eight hundred sixty-one million, eight hundred sixty-two thousand, seven hundred sixty-nine".