20145122461 has 2 divisors, whose sum is σ = 20145122462. Its totient is φ = 20145122460.

The previous prime is 20145122441. The next prime is 20145122509. The reversal of 20145122461 is 16422154102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14479549561 + 5665572900 = 120331^2 + 75270^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20145122461 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20145122441) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10072561230 + 10072561231.

It is an arithmetic number, because the mean of its divisors is an integer number (10072561231).

Almost surely, 2^20145122461 is an apocalyptic number.

It is an amenable number.

20145122461 is a deficient number, since it is larger than the sum of its proper divisors (1).

20145122461 is an equidigital number, since it uses as much as digits as its factorization.

20145122461 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3840, while the sum is 28.

Adding to 20145122461 its reverse (16422154102), we get a palindrome (36567276563).

The spelling of 20145122461 in words is "twenty billion, one hundred forty-five million, one hundred twenty-two thousand, four hundred sixty-one".