51857147 has 4 divisors (see below), whose sum is σ = 52230360. Its totient is φ = 51483936.

The previous prime is 51857119. The next prime is 51857149. The reversal of 51857147 is 74175815.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 51857147 - 2⁸ = 51856891 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 51857147.

It is not an unprimeable number, because it can be changed into a prime (51857149) 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, 186398 + ... + 186675.

It is an arithmetic number, because the mean of its divisors is an integer number (13057590).

Almost surely, 2^51857147 is an apocalyptic number.

51857147 is a deficient number, since it is larger than the sum of its proper divisors (373213).

51857147 is a wasteful number, since it uses less digits than its factorization.

51857147 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 373212.

The product of its digits is 39200, while the sum is 38.

The square root of 51857147 is about 7201.1906654386. The cubic root of 51857147 is about 372.9090070744.

The spelling of 51857147 in words is "fifty-one million, eight hundred fifty-seven thousand, one hundred forty-seven".