51201520 has 20 divisors (see below), whose sum is σ = 119043720. Its totient is φ = 20480576.

The previous prime is 51201503. The next prime is 51201539. The reversal of 51201520 is 2510215.

It is a tau number, because it is divible by the number of its divisors (20).

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a junction number, because it is equal to n+sod(n) for n = 51201494 and 51201503.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 319930 + ... + 320089.

It is an arithmetic number, because the mean of its divisors is an integer number (5952186).

Almost surely, 2^51201520 is an apocalyptic number.

It is an amenable number.

51201520 is an abundant number, since it is smaller than the sum of its proper divisors (67842200).

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

51201520 is a wasteful number, since it uses less digits than its factorization.

51201520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 640032 (or 640026 counting only the distinct ones).

The product of its (nonzero) digits is 100, while the sum is 16.

The square root of 51201520 is about 7155.5237404400. The cubic root of 51201520 is about 371.3307812438.

Adding to 51201520 its reverse (2510215), we get a palindrome (53711735).

The spelling of 51201520 in words is "fifty-one million, two hundred one thousand, five hundred twenty".