20123440061 has 2 divisors, whose sum is σ = 20123440062. Its totient is φ = 20123440060.

The previous prime is 20123440049. The next prime is 20123440067. The reversal of 20123440061 is 16004432102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16055424100 + 4068015961 = 126710^2 + 63781^2 .

It is a cyclic number.

It is not a de Polignac number, because 20123440061 - 2³⁰ = 19049698237 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20123440067) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10061720030 + 10061720031.

It is an arithmetic number, because the mean of its divisors is an integer number (10061720031).

Almost surely, 2^20123440061 is an apocalyptic number.

It is an amenable number.

20123440061 is a deficient number, since it is larger than the sum of its proper divisors (1).

20123440061 is an equidigital number, since it uses as much as digits as its factorization.

20123440061 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1152, while the sum is 23.

Adding to 20123440061 its reverse (16004432102), we get a palindrome (36127872163).

The spelling of 20123440061 in words is "twenty billion, one hundred twenty-three million, four hundred forty thousand, sixty-one".