51615872 has 64 divisors (see below), whose sum is σ = 128226240. Its totient is φ = 20106240.

The previous prime is 51615871. The next prime is 51615881. The reversal of 51615872 is 27851615.

It is a tau number, because it is divible by the number of its divisors (64).

It is not an unprimeable number, because it can be changed into a prime (51615871) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7238 + ... + 12474.

It is an arithmetic number, because the mean of its divisors is an integer number (2003535).

Almost surely, 2^51615872 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 51615872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (64113120).

51615872 is an abundant number, since it is smaller than the sum of its proper divisors (76610368).

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

51615872 is a wasteful number, since it uses less digits than its factorization.

51615872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5269 (or 5257 counting only the distinct ones).

The product of its digits is 16800, while the sum is 35.

The square root of 51615872 is about 7184.4186960394. The cubic root of 51615872 is about 372.3297650132.

The spelling of 51615872 in words is "fifty-one million, six hundred fifteen thousand, eight hundred seventy-two".