51637968549 has 24 divisors (see below), whose sum is σ = 75309068952. Its totient is φ = 34093086720.

The previous prime is 51637968533. The next prime is 51637968553. The reversal of 51637968549 is 94586973615.

51637968549 is a `hidden beast` number, since 5 + 16 + 3 + 79 + 6 + 8 + 549 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 519019524 + 51118949025 = 22782^2 + 226095^2 .

It is not a de Polignac number, because 51637968549 - 2⁴ = 51637968533 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51637268549) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1278829 + ... + 1318589.

It is an arithmetic number, because the mean of its divisors is an integer number (3137877873).

Almost surely, 2^51637968549 is an apocalyptic number.

It is an amenable number.

51637968549 is a deficient number, since it is larger than the sum of its proper divisors (23671100403).

51637968549 is a wasteful number, since it uses less digits than its factorization.

51637968549 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41157 (or 41154 counting only the distinct ones).

The product of its digits is 48988800, while the sum is 63.

The spelling of 51637968549 in words is "fifty-one billion, six hundred thirty-seven million, nine hundred sixty-eight thousand, five hundred forty-nine".