51516421332581 has 8 divisors (see below), whose sum is σ = 51573395260800. Its totient is φ = 51459462385312.

The previous prime is 51516421332547. The next prime is 51516421332583. The reversal of 51516421332581 is 18523312461515.

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

It is a cyclic number.

It is not a de Polignac number, because 51516421332581 - 2⁶ = 51516421332517 is a prime.

It is a super-2 number, since 2×51516421332581² (a number of 28 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51516421332583) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3143156 + ... + 10626018.

It is an arithmetic number, because the mean of its divisors is an integer number (6446674407600).

Almost surely, 2^{51516421332581} is an apocalyptic number.

It is an amenable number.

51516421332581 is a deficient number, since it is larger than the sum of its proper divisors (56973928219).

51516421332581 is a wasteful number, since it uses less digits than its factorization.

51516421332581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7490475.

The product of its digits is 864000, while the sum is 47.

The spelling of 51516421332581 in words is "fifty-one trillion, five hundred sixteen billion, four hundred twenty-one million, three hundred thirty-two thousand, five hundred eighty-one".