861604477 has 2 divisors, whose sum is σ = 861604478. Its totient is φ = 861604476.

The previous prime is 861604453. The next prime is 861604511. The reversal of 861604477 is 774406168.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 567344761 + 294259716 = 23819^2 + 17154^2 .

It is a cyclic number.

It is not a de Polignac number, because 861604477 - 2¹⁹ = 861080189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (861602477) 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, 430802238 + 430802239.

It is an arithmetic number, because the mean of its divisors is an integer number (430802239).

Almost surely, 2^861604477 is an apocalyptic number.

It is an amenable number.

861604477 is a deficient number, since it is larger than the sum of its proper divisors (1).

861604477 is an equidigital number, since it uses as much as digits as its factorization.

861604477 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 225792, while the sum is 43.

The square root of 861604477 is about 29353.0999555413. The cubic root of 861604477 is about 951.5595720228.

The spelling of 861604477 in words is "eight hundred sixty-one million, six hundred four thousand, four hundred seventy-seven".