51506464 has 48 divisors (see below), whose sum is σ = 108922968. Its totient is φ = 23887872.

The previous prime is 51506461. The next prime is 51506471. The reversal of 51506464 is 46460515.

It can be written as a sum of positive squares in 4 ways, for example, as 50296464 + 1210000 = 7092^2 + 1100^2 .

It is not an unprimeable number, because it can be changed into a prime (51506461) 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, 39064 + ... + 40360.

Almost surely, 2^51506464 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 51506464, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (54461484).

51506464 is an abundant number, since it is smaller than the sum of its proper divisors (57416504).

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

51506464 is a wasteful number, since it uses less digits than its factorization.

51506464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1397 (or 1389 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 31.

The square root of 51506464 is about 7176.8004012930. The cubic root of 51506464 is about 372.0665083228.

Adding to 51506464 its reverse (46460515), we get a palindrome (97966979).

The spelling of 51506464 in words is "fifty-one million, five hundred six thousand, four hundred sixty-four".