51207040 has 128 divisors (see below), whose sum is σ = 132192000. Its totient is φ = 18923520.

The previous prime is 51207029. The next prime is 51207041. The reversal of 51207040 is 4070215.

It is a tau number, because it is divible by the number of its divisors (128).

51207040 is a modest number, since divided by 7040 gives 5120 as remainder.

It is a junction number, because it is equal to n+sod(n) for n = 51206999 and 51207017.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51207041) 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 15 ways as a sum of consecutive naturals, for example, 575316 + ... + 575404.

It is an arithmetic number, because the mean of its divisors is an integer number (1032750).

Almost surely, 2^51207040 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 51207040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (66096000).

51207040 is an abundant number, since it is smaller than the sum of its proper divisors (80984960).

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

51207040 is a wasteful number, since it uses less digits than its factorization.

51207040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 168 (or 156 counting only the distinct ones).

The product of its (nonzero) digits is 280, while the sum is 19.

The square root of 51207040 is about 7155.9094460453. The cubic root of 51207040 is about 371.3441250681.

Adding to 51207040 its reverse (4070215), we get a palindrome (55277255).

The spelling of 51207040 in words is "fifty-one million, two hundred seven thousand, forty".