20005111464521 has 2 divisors, whose sum is σ = 20005111464522. Its totient is φ = 20005111464520.

The previous prime is 20005111464493. The next prime is 20005111464593. The reversal of 20005111464521 is 12546411150002.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17398617457225 + 2606494007296 = 4171165^2 + 1614464^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20005111464521 is a prime.

It is not a weakly prime, because it can be changed into another prime (20005111464721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10002555732260 + 10002555732261.

It is an arithmetic number, because the mean of its divisors is an integer number (10002555732261).

Almost surely, 2^{20005111464521} is an apocalyptic number.

It is an amenable number.

20005111464521 is a deficient number, since it is larger than the sum of its proper divisors (1).

20005111464521 is an equidigital number, since it uses as much as digits as its factorization.

20005111464521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9600, while the sum is 32.

The spelling of 20005111464521 in words is "twenty trillion, five billion, one hundred eleven million, four hundred sixty-four thousand, five hundred twenty-one".