51040820 has 12 divisors (see below), whose sum is σ = 107185764. Its totient is φ = 20416320.

The previous prime is 51040813. The next prime is 51040831. The reversal of 51040820 is 2804015.

It can be written as a sum of positive squares in 2 ways, for example, as 14776336 + 36264484 = 3844^2 + 6022^2 .

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 2552041 = 51040820 / (5 + 1 + 0 + 4 + 0 + 8 + 2 + 0).

It is a junction number, because it is equal to n+sod(n) for n = 51040792 and 51040801.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1276001 + ... + 1276040.

It is an arithmetic number, because the mean of its divisors is an integer number (8932147).

Almost surely, 2^51040820 is an apocalyptic number.

It is an amenable number.

51040820 is an abundant number, since it is smaller than the sum of its proper divisors (56144944).

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

51040820 is a wasteful number, since it uses less digits than its factorization.

51040820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2552050 (or 2552048 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 20.

The square root of 51040820 is about 7144.2858285486. The cubic root of 51040820 is about 370.9418904782.

Adding to 51040820 its reverse (2804015), we get a palindrome (53844835).

The spelling of 51040820 in words is "fifty-one million, forty thousand, eight hundred twenty".