51445240 has 64 divisors (see below), whose sum is σ = 144322560. Its totient is φ = 16033920.

The previous prime is 51445231. The next prime is 51445297. The reversal of 51445240 is 4254415.

It is a happy number.

It is a super-2 number, since 2×51445240² = 5293225437315200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5272 + ... + 11431.

It is an arithmetic number, because the mean of its divisors is an integer number (2255040).

Almost surely, 2^51445240 is an apocalyptic number.

It is an amenable number.

51445240 is an abundant number, since it is smaller than the sum of its proper divisors (92877320).

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

51445240 is a wasteful number, since it uses less digits than its factorization.

51445240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16732 (or 16728 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 25.

The square root of 51445240 is about 7172.5337224721. The cubic root of 51445240 is about 371.9190288947.

Adding to 51445240 its reverse (4254415), we get a palindrome (55699655).

It can be divided in two parts, 514 and 45240, that added together give a palindrome (45754).

The spelling of 51445240 in words is "fifty-one million, four hundred forty-five thousand, two hundred forty".