51000030 has 80 divisors (see below), whose sum is σ = 139043520. Its totient is φ = 13411008.

The previous prime is 50999999. The next prime is 51000041. The reversal of 51000030 is 3000015.

51000030 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 50999976 and 51000021.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 63592 + ... + 64388.

It is an arithmetic number, because the mean of its divisors is an integer number (1738044).

Almost surely, 2^51000030 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51000030, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (69521760).

51000030 is an abundant number, since it is smaller than the sum of its proper divisors (88043490).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51000030 is a wasteful number, since it uses less digits than its factorization.

51000030 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 895 (or 886 counting only the distinct ones).

The product of its (nonzero) digits is 15, while the sum is 9.

The square root of 51000030 is about 7141.4305289627. The cubic root of 51000030 is about 370.8430496409.

Subtracting from 51000030 its product of nonzero digits (15), we obtain a palindrome (51000015).

Adding to 51000030 its reverse (3000015), we get a palindrome (54000045).

The spelling of 51000030 in words is "fifty-one million, thirty", and thus it is an aban number and an uban number.