51431680 has 72 divisors (see below), whose sum is σ = 128624832. Its totient is φ = 19666944.

The previous prime is 51431663. The next prime is 51431687. The reversal of 51431680 is 8613415.

It is not an unprimeable number, because it can be changed into a prime (51431687) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28567 + ... + 30313.

It is an arithmetic number, because the mean of its divisors is an integer number (1786456).

Almost surely, 2^51431680 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 51431680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (64312416).

51431680 is an abundant number, since it is smaller than the sum of its proper divisors (77193152).

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

51431680 is a wasteful number, since it uses less digits than its factorization.

51431680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1791 (or 1777 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 28.

The square root of 51431680 is about 7171.5883875192. The cubic root of 51431680 is about 371.8863490640.

The spelling of 51431680 in words is "fifty-one million, four hundred thirty-one thousand, six hundred eighty".