51402520 has 64 divisors (see below), whose sum is σ = 127643040. Its totient is φ = 18508800.

The previous prime is 51402503. The next prime is 51402521. The reversal of 51402520 is 2520415.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51402521) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20115 + ... + 22525.

Almost surely, 2^51402520 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 51402520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (63821520).

51402520 is an abundant number, since it is smaller than the sum of its proper divisors (76240520).

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

51402520 is a wasteful number, since it uses less digits than its factorization.

51402520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2476 (or 2472 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 19.

The square root of 51402520 is about 7169.5550768510. Note that the first 3 decimals coincide. The cubic root of 51402520 is about 371.8160535055.

Adding to 51402520 its reverse (2520415), we get a palindrome (53922935).

The spelling of 51402520 in words is "fifty-one million, four hundred two thousand, five hundred twenty".