51442500 has 120 divisors (see below), whose sum is σ = 158324320. Its totient is φ = 12996000.

The previous prime is 51442499. The next prime is 51442507. The reversal of 51442500 is 524415.

It is a Saint-Exupery number, since it is equal to the product of the sides of a Pythagorean triangle: 475 × 285 × 380.

It is not an unprimeable number, because it can be changed into a prime (51442507) 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 39 ways as a sum of consecutive naturals, for example, 2707491 + ... + 2707509.

Almost surely, 2^51442500 is an apocalyptic number.

51442500 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51442500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (79162160).

51442500 is an abundant number, since it is smaller than the sum of its proper divisors (106881820).

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

51442500 is an equidigital number, since it uses as much as digits as its factorization.

51442500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84 (or 29 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 21.

The square root of 51442500 is about 7172.3427135072. The cubic root of 51442500 is about 371.9124259110.

Adding to 51442500 its reverse (524415), we get a palindrome (51966915).

The spelling of 51442500 in words is "fifty-one million, four hundred forty-two thousand, five hundred".