51390172 has 12 divisors (see below), whose sum is σ = 90143536. Its totient is φ = 25634880.

The previous prime is 51390161. The next prime is 51390173. The reversal of 51390172 is 27109315.

It is a self number, because there is not a number n which added to its sum of digits gives 51390172.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51390173) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13104 + ... + 16567.

Almost surely, 2^51390172 is an apocalyptic number.

It is an amenable number.

51390172 is a deficient number, since it is larger than the sum of its proper divisors (38753364).

51390172 is a wasteful number, since it uses less digits than its factorization.

51390172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30108 (or 30106 counting only the distinct ones).

The product of its (nonzero) digits is 1890, while the sum is 28.

The square root of 51390172 is about 7168.6938838257. The cubic root of 51390172 is about 371.7862783614.

Adding to 51390172 its reverse (27109315), we get a palindrome (78499487).

The spelling of 51390172 in words is "fifty-one million, three hundred ninety thousand, one hundred seventy-two".