51428440 has 96 divisors (see below), whose sum is σ = 141793200. Its totient is φ = 16692480.

The previous prime is 51428423. The next prime is 51428441. The reversal of 51428440 is 4482415.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a junction number, because it is equal to n+sod(n) for n = 51428399 and 51428408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51428441) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 36550 + ... + 37930.

Almost surely, 2^51428440 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 51428440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (70896600).

51428440 is an abundant number, since it is smaller than the sum of its proper divisors (90364760).

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

51428440 is a wasteful number, since it uses less digits than its factorization.

51428440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1425 (or 1414 counting only the distinct ones).

The product of its (nonzero) digits is 5120, while the sum is 28.

The square root of 51428440 is about 7171.3624925812. The cubic root of 51428440 is about 371.8785397587.

The spelling of 51428440 in words is "fifty-one million, four hundred twenty-eight thousand, four hundred forty".