51213504 has 56 divisors (see below), whose sum is σ = 136062720. Its totient is φ = 17000704.

The previous prime is 51213497. The next prime is 51213509. The reversal of 51213504 is 40531215.

It is not an unprimeable number, because it can be changed into a prime (51213509) 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 7 ways as a sum of consecutive naturals, for example, 68557 + ... + 69299.

Almost surely, 2^51213504 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 51213504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (68031360).

51213504 is an abundant number, since it is smaller than the sum of its proper divisors (84849216).

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

51213504 is a wasteful number, since it uses less digits than its factorization.

51213504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1117 (or 1107 counting only the distinct ones).

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

The square root of 51213504 is about 7156.3610864740. The cubic root of 51213504 is about 371.3597496608.

Adding to 51213504 its reverse (40531215), we get a palindrome (91744719).

The spelling of 51213504 in words is "fifty-one million, two hundred thirteen thousand, five hundred four".