51540561281 has 8 divisors (see below), whose sum is σ = 58039811328. Its totient is φ = 45343602000.

The previous prime is 51540561253. The next prime is 51540561353. The reversal of 51540561281 is 18216504515.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51540561281 is a prime.

It is a super-2 number, since 2×51540561281² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (51540561221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 75572330 + ... + 75573011.

It is an arithmetic number, because the mean of its divisors is an integer number (7254976416).

Almost surely, 2^51540561281 is an apocalyptic number.

It is an amenable number.

51540561281 is a deficient number, since it is larger than the sum of its proper divisors (6499250047).

51540561281 is a wasteful number, since it uses less digits than its factorization.

51540561281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 151145383.

The product of its (nonzero) digits is 48000, while the sum is 38.

The spelling of 51540561281 in words is "fifty-one billion, five hundred forty million, five hundred sixty-one thousand, two hundred eighty-one".