51161650000 has 120 divisors (see below), whose sum is σ = 125302214520. Its totient is φ = 20232960000.

The previous prime is 51161649997. The next prime is 51161650031. The reversal of 51161650000 is 5616115.

It can be written as a sum of positive squares in 12 ways, for example, as 50853858064 + 307791936 = 225508^2 + 17544^2 .

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4444252 + ... + 4455748.

It is an arithmetic number, because the mean of its divisors is an integer number (1044185121).

Almost surely, 2^51161650000 is an apocalyptic number.

51161650000 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51161650000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (62651107260).

51161650000 is an abundant number, since it is smaller than the sum of its proper divisors (74140564520).

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

51161650000 is an equidigital number, since it uses as much as digits as its factorization.

51161650000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11619 (or 11593 counting only the distinct ones).

The product of its (nonzero) digits is 900, while the sum is 25.

The spelling of 51161650000 in words is "fifty-one billion, one hundred sixty-one million, six hundred fifty thousand".