51999999999989 has 2 divisors, whose sum is σ = 51999999999990. Its totient is φ = 51999999999988.

The previous prime is 51999999999971. The next prime is 52000000000079. The reversal of 51999999999989 is 98999999999915.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 49874075616964 + 2125924383025 = 7062158^2 + 1458055^2 .

It is a cyclic number.

It is not a de Polignac number, because 51999999999989 - 2⁸ = 51999999999733 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51999999899989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25999999999994 + 25999999999995.

It is an arithmetic number, because the mean of its divisors is an integer number (25999999999995).

Almost surely, 2^{51999999999989} is an apocalyptic number.

It is an amenable number.

51999999999989 is a deficient number, since it is larger than the sum of its proper divisors (1).

51999999999989 is an equidigital number, since it uses as much as digits as its factorization.

51999999999989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1255242384360, while the sum is 113.

The spelling of 51999999999989 in words is "fifty-one trillion, nine hundred ninety-nine billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred eighty-nine".