51512172 has 12 divisors (see below), whose sum is σ = 120195096. Its totient is φ = 17170720.

The previous prime is 51512147. The next prime is 51512179. The reversal of 51512172 is 27121515.

It is a tau number, because it is divible by the number of its divisors (12).

It is not an unprimeable number, because it can be changed into a prime (51512179) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2146329 + ... + 2146352.

It is an arithmetic number, because the mean of its divisors is an integer number (10016258).

Almost surely, 2^51512172 is an apocalyptic number.

It is an amenable number.

51512172 is an abundant number, since it is smaller than the sum of its proper divisors (68682924).

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

51512172 is a wasteful number, since it uses less digits than its factorization.

51512172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4292688 (or 4292686 counting only the distinct ones).

The product of its digits is 700, while the sum is 24.

The square root of 51512172 is about 7177.1980605247. The cubic root of 51512172 is about 372.0802520812.

Adding to 51512172 its reverse (27121515), we get a palindrome (78633687).

The spelling of 51512172 in words is "fifty-one million, five hundred twelve thousand, one hundred seventy-two".