51978529949 has 2 divisors, whose sum is σ = 51978529950. Its totient is φ = 51978529948.

The previous prime is 51978529937. The next prime is 51978529973. The reversal of 51978529949 is 94992587915.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 36591864100 + 15386665849 = 191290^2 + 124043^2 .

It is a cyclic number.

It is not a de Polignac number, because 51978529949 - 2⁸ = 51978529693 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51978529249) 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, 25989264974 + 25989264975.

It is an arithmetic number, because the mean of its divisors is an integer number (25989264975).

Almost surely, 2^51978529949 is an apocalyptic number.

It is an amenable number.

51978529949 is a deficient number, since it is larger than the sum of its proper divisors (1).

51978529949 is an equidigital number, since it uses as much as digits as its factorization.

51978529949 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 73483200, while the sum is 68.

The spelling of 51978529949 in words is "fifty-one billion, nine hundred seventy-eight million, five hundred twenty-nine thousand, nine hundred forty-nine".