1861035825641 has 2 divisors, whose sum is σ = 1861035825642. Its totient is φ = 1861035825640.

The previous prime is 1861035825637. The next prime is 1861035825721. The reversal of 1861035825641 is 1465285301681.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1248126902416 + 612908923225 = 1117196^2 + 782885^2 .

It is a cyclic number.

It is not a de Polignac number, because 1861035825641 - 2² = 1861035825637 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1861035825641.

It is not a weakly prime, because it can be changed into another prime (1861035825941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 930517912820 + 930517912821.

It is an arithmetic number, because the mean of its divisors is an integer number (930517912821).

Almost surely, 2^{1861035825641} is an apocalyptic number.

It is an amenable number.

1861035825641 is a deficient number, since it is larger than the sum of its proper divisors (1).

1861035825641 is an equidigital number, since it uses as much as digits as its factorization.

1861035825641 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1382400, while the sum is 50.

The spelling of 1861035825641 in words is "one trillion, eight hundred sixty-one billion, thirty-five million, eight hundred twenty-five thousand, six hundred forty-one".