51665472 has 112 divisors (see below), whose sum is σ = 157276800. Its totient is φ = 16611840.

The previous prime is 51665461. The next prime is 51665473. The reversal of 51665472 is 27456615.

It is a happy number.

51665472 is a `hidden beast` number, since 51 + 66 + 547 + 2 = 666.

It is a super-3 number, since 3×51665472³ (a number of 24 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (51665473) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 49597 + ... + 50627.

Almost surely, 2^51665472 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 51665472, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (78638400).

51665472 is an abundant number, since it is smaller than the sum of its proper divisors (105611328).

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

51665472 is a wasteful number, since it uses less digits than its factorization.

51665472 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1081 (or 1065 counting only the distinct ones).

The product of its digits is 50400, while the sum is 36.

The square root of 51665472 is about 7187.8697817921. The cubic root of 51665472 is about 372.4489896067.

The spelling of 51665472 in words is "fifty-one million, six hundred sixty-five thousand, four hundred seventy-two".