505406165651 has 2 divisors, whose sum is σ = 505406165652. Its totient is φ = 505406165650.

The previous prime is 505406165603. The next prime is 505406165657. The reversal of 505406165651 is 156561604505.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 505406165651 - 2⁶ = 505406165587 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (505406165657) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 252703082825 + 252703082826.

It is an arithmetic number, because the mean of its divisors is an integer number (252703082826).

Almost surely, 2^505406165651 is an apocalyptic number.

505406165651 is a deficient number, since it is larger than the sum of its proper divisors (1).

505406165651 is an equidigital number, since it uses as much as digits as its factorization.

505406165651 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 540000, while the sum is 44.

The spelling of 505406165651 in words is "five hundred five billion, four hundred six million, one hundred sixty-five thousand, six hundred fifty-one".