50975978981 has 2 divisors, whose sum is σ = 50975978982. Its totient is φ = 50975978980.

The previous prime is 50975978971. The next prime is 50975979139. The reversal of 50975978981 is 18987957905.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 47422030756 + 3553948225 = 217766^2 + 59615^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-50975978981 is a prime.

It is a super-2 number, since 2×50975978981² (a number of 22 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (50975978941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25487989490 + 25487989491.

It is an arithmetic number, because the mean of its divisors is an integer number (25487989491).

Almost surely, 2^50975978981 is an apocalyptic number.

It is an amenable number.

50975978981 is a deficient number, since it is larger than the sum of its proper divisors (1).

50975978981 is an equidigital number, since it uses as much as digits as its factorization.

50975978981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 57153600, while the sum is 68.

The spelling of 50975978981 in words is "fifty billion, nine hundred seventy-five million, nine hundred seventy-eight thousand, nine hundred eighty-one".