861252397 has 2 divisors, whose sum is σ = 861252398. Its totient is φ = 861252396.

The previous prime is 861252389. The next prime is 861252409. The reversal of 861252397 is 793252168.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 674492841 + 186759556 = 25971^2 + 13666^2 .

It is a cyclic number.

It is not a de Polignac number, because 861252397 - 2³ = 861252389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (861252347) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 430626198 + 430626199.

It is an arithmetic number, because the mean of its divisors is an integer number (430626199).

Almost surely, 2^861252397 is an apocalyptic number.

It is an amenable number.

861252397 is a deficient number, since it is larger than the sum of its proper divisors (1).

861252397 is an equidigital number, since it uses as much as digits as its factorization.

861252397 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 181440, while the sum is 43.

The square root of 861252397 is about 29347.1020204721. The cubic root of 861252397 is about 951.4299414914.

It can be divided in two parts, 8612 and 52397, that added together give a square (61009 = 247²).

The spelling of 861252397 in words is "eight hundred sixty-one million, two hundred fifty-two thousand, three hundred ninety-seven".