51978529991 has 2 divisors, whose sum is σ = 51978529992. Its totient is φ = 51978529990.

The previous prime is 51978529973. The next prime is 51978530041. The reversal of 51978529991 is 19992587915.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 51978529991 - 2²⁶ = 51911421127 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51978519991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25989264995 + 25989264996.

It is an arithmetic number, because the mean of its divisors is an integer number (25989264996).

Almost surely, 2^51978529991 is an apocalyptic number.

51978529991 is a deficient number, since it is larger than the sum of its proper divisors (1).

51978529991 is an equidigital number, since it uses as much as digits as its factorization.

51978529991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18370800, while the sum is 65.

The spelling of 51978529991 in words is "fifty-one billion, nine hundred seventy-eight million, five hundred twenty-nine thousand, nine hundred ninety-one".