51651880 has 144 divisors (see below), whose sum is σ = 144635220. Its totient is φ = 16547328.

The previous prime is 51651869. The next prime is 51651881. The reversal of 51651880 is 8815615.

It can be written as a sum of positive squares in 2 ways, for example, as 51581124 + 70756 = 7182^2 + 266^2 .

It is a hoax number, since the sum of its digits (34) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (51651881) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 707524 + ... + 707596.

Almost surely, 2^51651880 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 51651880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (72317610).

51651880 is an abundant number, since it is smaller than the sum of its proper divisors (92983340).

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

51651880 is a wasteful number, since it uses less digits than its factorization.

51651880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136 (or 106 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 34.

The square root of 51651880 is about 7186.9242378085. The cubic root of 51651880 is about 372.4163258149.

The spelling of 51651880 in words is "fifty-one million, six hundred fifty-one thousand, eight hundred eighty".