51081420312485 has 4 divisors (see below), whose sum is σ = 61297704374988. Its totient is φ = 40865136249984.

The previous prime is 51081420312479. The next prime is 51081420312523. The reversal of 51081420312485 is 58421302418015.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 39504216716644 + 11577203595841 = 6285238^2 + 3402529^2 .

It is a cyclic number.

It is not a de Polignac number, because 51081420312485 - 2¹⁸ = 51081420050341 is a prime.

It is a super-2 number, since 2×51081420312485² (a number of 28 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5108142031244 + ... + 5108142031253.

It is an arithmetic number, because the mean of its divisors is an integer number (15324426093747).

Almost surely, 2^{51081420312485} is an apocalyptic number.

It is an amenable number.

51081420312485 is a deficient number, since it is larger than the sum of its proper divisors (10216284062503).

51081420312485 is a wasteful number, since it uses less digits than its factorization.

51081420312485 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10216284062502.

The product of its (nonzero) digits is 307200, while the sum is 44.

The spelling of 51081420312485 in words is "fifty-one trillion, eighty-one billion, four hundred twenty million, three hundred twelve thousand, four hundred eighty-five".