51145540 has 12 divisors (see below), whose sum is σ = 107405676. Its totient is φ = 20458208.

The previous prime is 51145519. The next prime is 51145553. The reversal of 51145540 is 4554115.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 9388096 + 41757444 = 3064^2 + 6462^2 .

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, 1278619 + ... + 1278658.

It is an arithmetic number, because the mean of its divisors is an integer number (8950473).

Almost surely, 2^51145540 is an apocalyptic number.

It is an amenable number.

51145540 is an abundant number, since it is smaller than the sum of its proper divisors (56260136).

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

51145540 is a wasteful number, since it uses less digits than its factorization.

51145540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2557286 (or 2557284 counting only the distinct ones).

The product of its (nonzero) digits is 2000, while the sum is 25.

The square root of 51145540 is about 7151.6110073186. The cubic root of 51145540 is about 371.1954032483.

Adding to 51145540 its reverse (4554115), we get a palindrome (55699655).

The spelling of 51145540 in words is "fifty-one million, one hundred forty-five thousand, five hundred forty".