861937249 has 2 divisors, whose sum is σ = 861937250. Its totient is φ = 861937248.

The previous prime is 861937199. The next prime is 861937289. The reversal of 861937249 is 942739168.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 599270400 + 262666849 = 24480^2 + 16207^2 .

It is a cyclic number.

It is not a de Polignac number, because 861937249 - 2¹¹ = 861935201 is a prime.

It is not a weakly prime, because it can be changed into another prime (861937289) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 430968624 + 430968625.

It is an arithmetic number, because the mean of its divisors is an integer number (430968625).

Almost surely, 2^861937249 is an apocalyptic number.

It is an amenable number.

861937249 is a deficient number, since it is larger than the sum of its proper divisors (1).

861937249 is an equidigital number, since it uses as much as digits as its factorization.

861937249 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 653184, while the sum is 49.

The square root of 861937249 is about 29358.7678385861. The cubic root of 861937249 is about 951.6820611822.

The spelling of 861937249 in words is "eight hundred sixty-one million, nine hundred thirty-seven thousand, two hundred forty-nine".