51404220 has 144 divisors (see below), whose sum is σ = 184923648. Its totient is φ = 11741760.

The previous prime is 51404219. The next prime is 51404237. The reversal of 51404220 is 2240415.

51404220 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 (18).

It is a junction number, because it is equal to n+sod(n) for n = 51404193 and 51404202.

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 47 ways as a sum of consecutive naturals, for example, 33265 + ... + 34775.

It is an arithmetic number, because the mean of its divisors is an integer number (1284192).

Almost surely, 2^51404220 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51404220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (92461824).

51404220 is an abundant number, since it is smaller than the sum of its proper divisors (133519428).

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

51404220 is a wasteful number, since it uses less digits than its factorization.

51404220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1542 (or 1528 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 51404220 is about 7169.6736327395. The cubic root of 51404220 is about 371.8201523987.

Adding to 51404220 its reverse (2240415), we get a palindrome (53644635).

It can be divided in two parts, 5 and 1404220, that added together give a square (1404225 = 1185²).

The spelling of 51404220 in words is "fifty-one million, four hundred four thousand, two hundred twenty".