51681872 has 40 divisors (see below), whose sum is σ = 111793440. Its totient is φ = 22942080.

The previous prime is 51681871. The next prime is 51681893. The reversal of 51681872 is 27818615.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51681871) 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, 4154 + ... + 10982.

It is an arithmetic number, because the mean of its divisors is an integer number (2794836).

Almost surely, 2^51681872 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 51681872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (55896720).

51681872 is an abundant number, since it is smaller than the sum of its proper divisors (60111568).

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

51681872 is a wasteful number, since it uses less digits than its factorization.

51681872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6891 (or 6885 counting only the distinct ones).

The product of its digits is 26880, while the sum is 38.

The square root of 51681872 is about 7189.0105021484. The cubic root of 51681872 is about 372.4883938549.

The spelling of 51681872 in words is "fifty-one million, six hundred eighty-one thousand, eight hundred seventy-two".