51491066544403 has 2 divisors, whose sum is σ = 51491066544404. Its totient is φ = 51491066544402.

The previous prime is 51491066544377. The next prime is 51491066544443. The reversal of 51491066544403 is 30444566019415.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51491066544403 is a prime.

It is not a weakly prime, because it can be changed into another prime (51491066544443) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25745533272201 + 25745533272202.

It is an arithmetic number, because the mean of its divisors is an integer number (25745533272202).

Almost surely, 2^{51491066544403} is an apocalyptic number.

51491066544403 is a deficient number, since it is larger than the sum of its proper divisors (1).

51491066544403 is an equidigital number, since it uses as much as digits as its factorization.

51491066544403 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6220800, while the sum is 52.

The spelling of 51491066544403 in words is "fifty-one trillion, four hundred ninety-one billion, sixty-six million, five hundred forty-four thousand, four hundred three".