51007720 has 16 divisors (see below), whose sum is σ = 114767460. Its totient is φ = 20403072.

The previous prime is 51007717. The next prime is 51007729. The reversal of 51007720 is 2770015.

It can be written as a sum of positive squares in 2 ways, for example, as 47251876 + 3755844 = 6874^2 + 1938^2 .

It is a junction number, because it is equal to n+sod(n) for n = 51007691 and 51007700.

It is not an unprimeable number, because it can be changed into a prime (51007729) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 637557 + ... + 637636.

Almost surely, 2^51007720 is an apocalyptic number.

It is an amenable number.

51007720 is an abundant number, since it is smaller than the sum of its proper divisors (63759740).

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

51007720 is a wasteful number, since it uses less digits than its factorization.

51007720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1275204 (or 1275200 counting only the distinct ones).

The product of its (nonzero) digits is 490, while the sum is 22.

The square root of 51007720 is about 7141.9689162023. The cubic root of 51007720 is about 370.8616877981.

Adding to 51007720 its reverse (2770015), we get a palindrome (53777735).

The spelling of 51007720 in words is "fifty-one million, seven thousand, seven hundred twenty".