51800087 has 4 divisors (see below), whose sum is σ = 51828000. Its totient is φ = 51772176.

The previous prime is 51800083. The next prime is 51800093. The reversal of 51800087 is 78000815.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78000815 = 5 ⋅15600163.

It is a cyclic number.

It is not a de Polignac number, because 51800087 - 2² = 51800083 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51800081) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10958 + ... + 14955.

It is an arithmetic number, because the mean of its divisors is an integer number (12957000).

Almost surely, 2^51800087 is an apocalyptic number.

51800087 is a deficient number, since it is larger than the sum of its proper divisors (27913).

51800087 is a wasteful number, since it uses less digits than its factorization.

51800087 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27912.

The product of its (nonzero) digits is 2240, while the sum is 29.

The square root of 51800087 is about 7197.2277301750. The cubic root of 51800087 is about 372.7721824944.

The spelling of 51800087 in words is "fifty-one million, eight hundred thousand, eighty-seven".