51315420 has 48 divisors (see below), whose sum is σ = 154738080. Its totient is φ = 12631296.

The previous prime is 51315403. The next prime is 51315431. The reversal of 51315420 is 2451315.

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, 32115 + ... + 33674.

It is an arithmetic number, because the mean of its divisors is an integer number (3223710).

Almost surely, 2^51315420 is an apocalyptic number.

It is an amenable number.

51315420 is an abundant number, since it is smaller than the sum of its proper divisors (103422660).

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

51315420 is a wasteful number, since it uses less digits than its factorization.

51315420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65814 (or 65812 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 21.

The square root of 51315420 is about 7163.4782054530. The cubic root of 51315420 is about 371.6059244599.

Adding to 51315420 its reverse (2451315), we get a palindrome (53766735).

The spelling of 51315420 in words is "fifty-one million, three hundred fifteen thousand, four hundred twenty".