51138055222581 has 8 divisors (see below), whose sum is σ = 68192094376224. Its totient is φ = 34088026442000.

The previous prime is 51138055222537. The next prime is 51138055222589. The reversal of 51138055222581 is 18522255083115.

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 51138055222581 - 2⁶ = 51138055222517 is a prime.

It is a super-2 number, since 2×51138055222581² (a number of 28 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 51138055222581.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51138055222589) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1002563511 + ... + 1002614516.

It is an arithmetic number, because the mean of its divisors is an integer number (8524011797028).

Almost surely, 2^{51138055222581} is an apocalyptic number.

It is an amenable number.

51138055222581 is a deficient number, since it is larger than the sum of its proper divisors (17054039153643).

51138055222581 is a wasteful number, since it uses less digits than its factorization.

51138055222581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2005186531.

The product of its (nonzero) digits is 960000, while the sum is 48.

The spelling of 51138055222581 in words is "fifty-one trillion, one hundred thirty-eight billion, fifty-five million, two hundred twenty-two thousand, five hundred eighty-one".