51320550 has 48 divisors (see below), whose sum is σ = 128116800. Its totient is φ = 13595040.

The previous prime is 51320527. The next prime is 51320597. The reversal of 51320550 is 5502315.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 23401 + ... + 25499.

It is an arithmetic number, because the mean of its divisors is an integer number (2669100).

Almost surely, 2^51320550 is an apocalyptic number.

51320550 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 51320550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (64058400).

51320550 is an abundant number, since it is smaller than the sum of its proper divisors (76796250).

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

51320550 is a wasteful number, since it uses less digits than its factorization.

51320550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2277 (or 2272 counting only the distinct ones).

The product of its (nonzero) digits is 750, while the sum is 21.

The square root of 51320550 is about 7163.8362627855. The cubic root of 51320550 is about 371.6183071893.

Adding to 51320550 its reverse (5502315), we get a palindrome (56822865).

The spelling of 51320550 in words is "fifty-one million, three hundred twenty thousand, five hundred fifty".