51247145 has 4 divisors (see below), whose sum is σ = 61496580. Its totient is φ = 40997712.

The previous prime is 51247139. The next prime is 51247169. The reversal of 51247145 is 54174215.

51247145 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in 2 ways, for example, as 17106496 + 34140649 = 4136^2 + 5843^2 .

It is a cyclic number.

It is not a de Polignac number, because 51247145 - 2¹⁴ = 51230761 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5124710 + ... + 5124719.

It is an arithmetic number, because the mean of its divisors is an integer number (15374145).

Almost surely, 2^51247145 is an apocalyptic number.

It is an amenable number.

51247145 is a deficient number, since it is larger than the sum of its proper divisors (10249435).

51247145 is a wasteful number, since it uses less digits than its factorization.

51247145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10249434.

The product of its digits is 5600, while the sum is 29.

The square root of 51247145 is about 7158.7111270116. The cubic root of 51247145 is about 371.4410444881.

The spelling of 51247145 in words is "fifty-one million, two hundred forty-seven thousand, one hundred forty-five".