11861902861961 has 2 divisors, whose sum is σ = 11861902861962. Its totient is φ = 11861902861960.

The previous prime is 11861902861873. The next prime is 11861902861973. The reversal of 11861902861961 is 16916820916811.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9214448451961 + 2647454410000 = 3035531^2 + 1627100^2 .

It is a cyclic number.

It is not a de Polignac number, because 11861902861961 - 2³⁰ = 11860829120137 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 11861902861961.

It is not a weakly prime, because it can be changed into another prime (11861902861261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5930951430980 + 5930951430981.

It is an arithmetic number, because the mean of its divisors is an integer number (5930951430981).

Almost surely, 2^{11861902861961} is an apocalyptic number.

It is an amenable number.

11861902861961 is a deficient number, since it is larger than the sum of its proper divisors (1).

11861902861961 is an equidigital number, since it uses as much as digits as its factorization.

11861902861961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2239488, while the sum is 59.

The spelling of 11861902861961 in words is "eleven trillion, eight hundred sixty-one billion, nine hundred two million, eight hundred sixty-one thousand, nine hundred sixty-one".