511984621961 has 2 divisors, whose sum is σ = 511984621962. Its totient is φ = 511984621960.

The previous prime is 511984621927. The next prime is 511984621979. The reversal of 511984621961 is 169126489115.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 511984611961 + 10000 = 715531^2 + 100^2 .

It is a cyclic number.

It is not a de Polignac number, because 511984621961 - 2²⁶ = 511917513097 is a prime.

It is not a weakly prime, because it can be changed into another prime (511984621061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 255992310980 + 255992310981.

It is an arithmetic number, because the mean of its divisors is an integer number (255992310981).

Almost surely, 2^511984621961 is an apocalyptic number.

It is an amenable number.

511984621961 is a deficient number, since it is larger than the sum of its proper divisors (1).

511984621961 is an equidigital number, since it uses as much as digits as its factorization.

511984621961 is an evil number, because the sum of its binary digits is even.

The product of its digits is 933120, while the sum is 53.

The spelling of 511984621961 in words is "five hundred eleven billion, nine hundred eighty-four million, six hundred twenty-one thousand, nine hundred sixty-one".