861028003261 has 2 divisors, whose sum is σ = 861028003262. Its totient is φ = 861028003260.

The previous prime is 861028003237. The next prime is 861028003291. The reversal of 861028003261 is 162300820168.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 707760451225 + 153267552036 = 841285^2 + 391494^2 .

It is a cyclic number.

It is not a de Polignac number, because 861028003261 - 2⁷ = 861028003133 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 861028003261.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (861028003291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 430514001630 + 430514001631.

It is an arithmetic number, because the mean of its divisors is an integer number (430514001631).

Almost surely, 2^861028003261 is an apocalyptic number.

It is an amenable number.

861028003261 is a deficient number, since it is larger than the sum of its proper divisors (1).

861028003261 is an equidigital number, since it uses as much as digits as its factorization.

861028003261 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27648, while the sum is 37.

The spelling of 861028003261 in words is "eight hundred sixty-one billion, twenty-eight million, three thousand, two hundred sixty-one".