20389342887961 has 2 divisors, whose sum is σ = 20389342887962. Its totient is φ = 20389342887960.

The previous prime is 20389342887941. The next prime is 20389342888121. The reversal of 20389342887961 is 16978824398302.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20389342887936 + 25 = 4515456^2 + 5^2 .

It is a cyclic number.

It is not a de Polignac number, because 20389342887961 - 2²⁵ = 20389309333529 is a prime.

It is not a weakly prime, because it can be changed into another prime (20389342887941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10194671443980 + 10194671443981.

It is an arithmetic number, because the mean of its divisors is an integer number (10194671443981).

Almost surely, 2^{20389342887961} is an apocalyptic number.

It is an amenable number.

20389342887961 is a deficient number, since it is larger than the sum of its proper divisors (1).

20389342887961 is an equidigital number, since it uses as much as digits as its factorization.

20389342887961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 250822656, while the sum is 70.

The spelling of 20389342887961 in words is "twenty trillion, three hundred eighty-nine billion, three hundred forty-two million, eight hundred eighty-seven thousand, nine hundred sixty-one".