51352561649 has 2 divisors, whose sum is σ = 51352561650. Its totient is φ = 51352561648.

The previous prime is 51352561609. The next prime is 51352561661. The reversal of 51352561649 is 94616525315.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 38097184225 + 13255377424 = 195185^2 + 115132^2 .

It is a cyclic number.

It is not a de Polignac number, because 51352561649 - 2²⁴ = 51335784433 is a prime.

It is not a weakly prime, because it can be changed into another prime (51352561609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25676280824 + 25676280825.

It is an arithmetic number, because the mean of its divisors is an integer number (25676280825).

Almost surely, 2^51352561649 is an apocalyptic number.

It is an amenable number.

51352561649 is a deficient number, since it is larger than the sum of its proper divisors (1).

51352561649 is an equidigital number, since it uses as much as digits as its factorization.

51352561649 is an evil number, because the sum of its binary digits is even.

The product of its digits is 972000, while the sum is 47.

The spelling of 51352561649 in words is "fifty-one billion, three hundred fifty-two million, five hundred sixty-one thousand, six hundred forty-nine".